Working so much at 9+ weeks , need advice

I could be anywhere from 9-11 weeks. I have irregular periods so I'm not too sure how far along I am. My first apt is 11/3. Anyways my job are long 12-13 hours shifts. Working 40 hours is a lot for me only because of my constant nausea and vomiting. It's been so bad I needed an IV twice already and got prescribed promethazine which doesn't help much. Moving around a lot makes it worse . I dont know how to tell my obgyn if it's possible to write a work note to cut my hours in half.. I just feel like I'm being a whiny baby but constantly throwing up and feeling nausea is really hard. Am I being a baby? Should I just suck it up and continue to work 40-50 hrs a week? As soon as this nausea goes away I'll be more then happy to work a lot but not like this. We are already short staffed at my work as it is so I know my manager will not be happy but she puts only 30 hrs a week. Ughhh help please I need advice .. I just have a feeling my doctor is gonna be like your fine continue to work it will go away.