How early is too early for Braxton hicks???

I've been trying to read up on Braxton hicks contractions. This is my second pregnancy and with my first I felt them early and often maybe 24 weeks-ish. I was told drink no less than 64oz of water a day and that should keep them at bay. Well, it did a little. 
This pregnancy I'm currently 16+5 and been feeling them all day. I upped my water intake and took it easer than normal. I would of thought 16wks is a little too early. 
Any thoughts?!?