UTI or just sore after sex?

Hi everyone. I was having sex with my boyfriend earlier today, and it was great, I was on top of him, he was sitting on the couch and I was bouncing a fair bit. After he finished I sat on top for a while and then started to feel cramps and pain in my lower abdomen and back. I went to pee and it hurt really badly. I probably have a bad uti, I’ve never had one before but I just wanted to know what to do (doctors, at home remedies etc) or if I could have just hurt myself during the sex. It has been hurting for almost 12 hours now and hasn’t really stopped, I had some ural tea.