NOT A UTI, CAN'T be an STD. HELP. SCARED.

So I'm 17 and I've been having UTI symptoms for probably 2-3 weeks. I've had one before and the doctors office I went so gave me antibiotics. I took them and they worked. Recently though, October 1st, I went to try to get fix my problem at Planned Parenthood and go get some antibiotics for what I thought was a UTI. I had all the same symptoms, lower abdomen pain, some lower back pain, and a somewhat urgency to pee, but  it wasn't something that always happened. My pee also has a very strong odor. Anyway, the doctor told me that I didn't have a UTI, so she did took a swab, came back said I didn't have any infections at all. But she said she would send it in the lab for STD testing. That was the last thing on my list. I'm in a mutually monogamous relationship. And yes, I trust my boyfriend. But I still questioned him. Anyway, this woman scared me. Where could I have gotten an STD from?? I still haven't gotten my lab results back and I'm so scared I can't even sleep. After my visit at Planned Parenthood my vagina has been feeling irritated, but not itchy, I don't have any discharge and when I tried to have sex it hurt so bad, which has never happened before until I left Planned Parenthood.  She didn't even tell me how long my results would take it's been 8 days and I haven't received any information. But I'm still in pain. Please someone, could this really be a STD? Also, I'm on Depo. Please I'm scared.