discharge?!?

Sorry this is a tmi post! What type of discharge is normal in the second trimester? Sometimes it's creamy but I always feel wet down there.  A few times a day I'll even have a little patch, like watery, of wetness on my undies? I don't know if it's a little urine or discharge, or even a leak. Is this normal or could I have a amniotic leak?  Going to the dr today and planning on asking, but any advice appreciated! Oh I'm a FTM 21 weeks with twins.