Birth control

I just got back on birth control & it's been 2 weeks. I take it before going to bed and I just feel so horrible before sleeping and when I wake up every morning. I've been tossing and turning waking up in the middle of the night, feeling very nauseous and dehydrated, I get bad stomach aches in bed (before sleeping & once I wake up) and every time I try to eat I get nauseous and lose my appetite. Has anything like this happened to anyone else? Is this normal?