I cant pee!

I have this never ending feeling like I am going to pee my pants but when I go to pee only a little comes out. Its been going on for a week. But I've also had a sharp pain in my pelvic for a little over a month that feels like I am being stabbed! I don't know what's wrong. I am not too sure if the fact that I had sex Wednesday or that I went to the er and was diagnosed with a UTI last month but I wasn't given any antibiotics has anything to do with this but it might help, Idk. I just really need to pee. Its causing me to not be able to sleep. Ik that yall arent doctors but one of you might have gone through the same thing. I told my parents about the pain but they said it was nothing. What could all this be??