Is There Any Possibility Of Pregnancy Even After Having Periods? Could I Have UTI?

Hello, my name is Mireya and I'm 15 years old. I had intercourse for the first time on October 31st of this year. We used a condom. A few weeks ago, me and my boyfriend did again on a Saturday but he took off the condom. We then took a shower after, but he never ejaculated inside of me. The following Monday, we did again without any protection at all. He ejaculated near my vagina and it then slid down into it. We got scared so I took the Plan B One Step pill and we hadn't done anything since. Until this Friday, 2 days ago, we had intercourse for a good minute and a half but no ejaculation occured near my vagina. I got my period 2 Saturdays ago and since the middle of ot, I've been having frequent urges to urinate but not much urine comes out. I also have been having groin pain from a pulled groin muscle. My period was later than expected and it lasted much longer than any other period that I've ever had. Is there a possibility that I'm pregnant even though I had my period? Could I have a UTI? My mom doesn't know I'm sexually active and I'm scared that if I go to the doctor, the doctor will tell her something. I'm unsure of what to do.