Help!

I'm almost 3 weeks pp & I'm having a lot of pain inside my vagina & can't pee. I went to the ER almost 2 weeks ago and was told I had a uti and was given a week of antibiotics. Well I took all the meds on time and still feel the same discomfort. I went to the doc today and was told to pee in a cup. I couldn't go after 2 hours so I was sent home with the cup and to bring it back. There about to close and I still can't pee & I'm in alot of pain in my vagina. What do I do? Go to the ER? Or wait it out? Thanks!