Incredibly thirsty

I'm 6.4 weeks pregnant and feel incredibly thirsty. I'm not diabetic, I get routine blood work every year and obgyn just did more routine blood work yesterday so I'm sure if for some reason something has changed i will find out soon. I've always been pretty good about drinking enough water. I'm not drinking any liquid besides water and drink 2-3 liters a day but am finding myself still feeling dehydrated. Now drinking closer to over 4 liters. Anyone else?