All day today, my bladder has felt really full, but not been nearly as full as i thought when I actually get to pee...

Fast forward to 5 this morning. My urine is pretty much odorless, and it was just leaking out, or trickling, and even when I pushed like normal to pee, I could not make the flow come out faster...I'm 26 weeks pregnant, and worried. I have a doc appt,on weds and since its like 5 am on a Sunday, can't call my doc. Anyone else ever have this?