Random nausea

Mariah • Nerd. MCU <3
So. In week 36. And i was really thirsty. So I decided I wanted to drink some apple juice! It tasted marvelous. Then, as soon as I put the lid on, I got so nauseous I had to sit. And automatically got a headache. Anyone know why?? I've been drinking apple juice my entire pregnancy with no problem. Until today.