Weird urine? Help!

Lydia
Ok, so first things first, I don't think I have a UTI.  I've had one before and this is different, but semi similar.
So every two or three days I'll suddenly have a few hours where I just can't get rid of the urge to pee, even after I go.  Urine is cloudy, but no burning, no weird smell.  This is usually something that happens in the morning.  I freak out, because I don't want a UTI, and plan on swinging by the clinic after school.  However, by that time, urine is clear, and I have no more urge to pee.  Totally back to normal.
Any ideas?