What to do when you can't remember anything?

Hi. I don't really know how to start this ramble off, because I'm genuinely so lost right now it's crazy. My entire world has been flipped upside down and I don't know how to fix it. This will have mentions of rape in it, so please don't read if you're triggered by these kinds of things. This is somewhat TMI so I'm sorry if I violate any rules. I'll take this post down if needed. Please be kind to me, as I am reaching out in hopes of getting advice or any sort of support.

I'm a freshly 17 year old girl. This is just a burner account I made specifically for this post. I had been having issues related to my health lately and ended up going to a gynecologist. I get swabbed, yada yada, and about two weeks later, I get my test results back. I have an STI (Mycoplasma genitalium) but I've never had sex before. For context, I already have sexual trauma (I've been exploited sexually online when I was 13). However, I have no recollection of ever being raped or sexually assaulted in any way. I've had the issue I went to the gyno for for at least 2-3 years (since freshman year and younger) but I never thought it was an STI/STD. The only way I could've gotten this infection was through sex, and I'm horrified about this realization that I have been violated without remembering a single detail.

I am in therapy for many reasons and have an appointment tomorrow. I'm terrified and don't even know where to begin. The shock of knowing you've been violated without remembering a single detail is something I can't even describe. I don't know what to do, or if I even believe it could've happened. There's no other way I could've gotten the infection. I feel sick. Any advice would help. I just want to know if anyone's gone through a similar situation and what they did, if that makes sense. Thanks.