Okay, here's my dilemma. I am 16 and sexually active. I've been with my girlfriend for a year and a half. We've used to have sex perfectly with no problems until about a couple of months ago. Now, I can't even get an erection and I don't ever feel horny anymore at all. I ask all my friends if they have this problem but they say no, they can get erections very quickly. I'm having a lot of trouble with this because I thought at this age teens are able to get it up quick and easy. I don't know if it's a testosterone problem or not but it's starting to wear on me. I'm in good shape, but I smoke a little bit. Basically, I've completely lost my sexual appetite. This isn't right. Someone help!
A couple of years ago, I learned to knit and I got really really interested in knitting. Anytime I was sitting still (and sometimes when I was moving) I was knitting. But then, after a while, I sorta stopped getting that urge to knit everytime I sat still. It wasn't that I didn't enjoy knitting. It wasn't that I had broken a hand. It wasn't even that I was bored. I just didn't really feel that need to knit fast and furious anymore. There were other things going on in my life at the time as well. I became interested in other things, I had other things that I needed to do that were more pressing than knitting. So I stopped entirely for a while. Eventually, I picked my needles back up again and started back to knitting.
Why did I tell you that story? Because sex is kinda like knitting. Not in literal terms, but because just like my interest in knitting, one's interest in sex can (and does) wax and wane throughout life. There will be times where sex is more at the forefront for you, where it's a priority. And there are going to be times where it just isn't that big of a deal or where you don't feel the same urge to be sexually active.
There can be any number of causes for a change in your interest in sex. Sure, physical issues (like hormonal changes, illnesses, pregnancy, depression, etc.) can impact the sex you're having or the sex you want to have, but that's not the only thing. Sometimes there are other things going on in our lives at any given time that take priority or take such an amount of our focus away that there's just not room (or sometimes time) left for sex. The day to day stresses (jobs, cars, friends, etc.) or really big changes or stressors can change things for us. We may just have other things that we need to do or to deal with, and sex is certainly an "optional activity" so it's something that we know we can put on hold while we handle our other stuff. Sometimes there are also things going on in our relationships that make us want to be less sexual with a partner. It can be a need to focus on other parts of the relationship, or if something is wrong in the relationship that can also bleed over into our sex lives. If there are concerns about pregnancy or about "getting caught" or things like that, it can impact our desire for sexual activity. Sometimes, we just really don't know why we are not interested in sex anymore, but we just aren't for a while. We may never consciously know why we wanted to take a break from sex for a while.
The good news is that this is likely nothing to worry about. Every person goes through those sorts of changes in sexual interest. You'll probably find, as you go through life, that this just happens occasionally. It's normal, even if your friends are telling you that they haven't had this happen. (It may be that your friends just haven't experienced this yet. Or, perhaps they're not being strictly honest with you. Often people don't want to talk about the downs in their sex life.)
So what can you do now? Well, first off, you can explore on your own why this might be happening. Is there something unresolved in your relationship that's causing issues? Are you having worries about STIs or pregnancy? Are there other stresses in your life that are having an impact? Even if you do look at all of those things and find that everything is okay, don't worry. The second thing to do is to stop stressing over this. The more you stress, the less likely you'll be interested in sex. Just accept the fact that maybe during this point in your life, sex just isn't the priority. Focus on other things in your life and your relationship that you enjoy. Take up a new hobby, learn a new sport, or volunteer somewhere. Doing things that are good for your body, mind, and spirit are never a bad thing! There are also many other (non-sexual) things you can do with your partner that are still increasing intimacy but not putting that sexual pressure on yourself. You can just hold hands or snuggle, have good talks, or simply be together quietly and still be fulfilling that need for closeness.
This will likely pass soon enough. The less pressure you put on yourself about it, the better off you will be.
Don't put yourself in a position where the sex itself is becoming a stressful thing instead of an enjoyable thing. You will probably eventually start to feel interested in sex again. I can't tell you exactly how long that may be - it could be 2 days, it could be 2 weeks, it could be 2 months. It's just hard to say. If this goes on for a long time or if you start having other physical issues going on, then it's time to head to your doctor and make sure everything really is physically okay with you right now. It's unusual for young men to have that famous ED (erectile dysfunction) that we hear about on so many commercials, so it's very unlikely that is the issue for you or that you would need a medication to treat it. (Do NOT be temped into taking any of those medications recreationally or without a doctor's specific instructions. They are made to treat a very specific cause for ED and can be dangerous when taken incorrectly or by folks who don't need them.) It is much less likely that there is a physical reason for what you are experiencing, though you are welcome to speak with your doctor about your concerns whenever you'd like. I'd probably suggest riding this out for a while and seeing if things change on their own (since this is a natural part of things) before thinking it's a physical issue (especially since you're reporting being in good health otherwise).
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