I've been on T for over 5 years now, no menstrual cycles although I did seem to have what appeared to be a small one (or just genital bleeding) when I had gonorrhea a few months ago, though this only lasted maybe 2 days. My boyfriend came inside me the other night, and afterwards I began worrying. We did some research and it seems like I should be fine since I've been on T so long. However I still worry somewhat. That is something I would never, under any circumstances, want to go through. Also, I thought the OTC tests were valid to do after the first day or so, but I have also heard you should wait 10 days. Any experience or thoughts appreciated.

Statistically speaking you should be fine, because it's difficult for anyone to fall pregnant. On average, cis women take 11 months to successfully conceive - and that's without the use of T, and whilst trying regularly and deliberately. However...

I'm sorry to tell you this, but no matter how long you've been on T there's still a risk that you might be ovulating even if you aren't menstruating, if you haven't had a hysto/oopho. It's entirely possible for trans guys to ovulate without menstruating, and quite a few have fallen pregnant unexpectedly after having been on T for years. And because there are no tell-tale clues (like menstruation) to tell you that it's happened, there's no way of knowing if you've ovulated. That's why we're supposed to keep using contraception whenever we have sex with someone who might be able to impregnate us. If this is something you definitely don't want to go through, you need to use protection every time.

OTC tests detect a hormone called HCG that is produced by the embryo; some of them are sensitive enough to detect traces of HCG within a few days, but they're far more accurate if you wait longer because the concentration of HCG gets stronger with time. So by all means do one of the early tests now, but be sure to repeat it in a couple of weeks' time just to be safe.

Good luck.