Coming early?

I'm 33 weeks with #4 on Friday, And I'm starting to wonder how early this baby's coming. Although my contractions are sporadic, they're painful, and they're actually my entire uterus instead of just the lower half like they say are the Braxton Hicks. Also, every time I contract, I "let down". I checked myself in the shower this morning, pretty sure I'm starting to thin even though baby hasn't dropped yet. I don't remember it being like this for any of the others even though they were a week or 2 early! Has anyone else had signs like this? I have my next OB appt on Friday and will be bringing it up, just wondering about personal experiences?