laying on your back

Sidney
So I have a really bitchy, OB. She makes me feel like a f****** moron all the time for asking questions about my high risk pregnancy... that's a long story for another time...
She asked me what position I fall asleep and wake up in. I'm 17 weeks 2 days pregnant and I told her that I fall asleep on my side but I tend to wake up on my back. And she took a huge sigh, rolled her eyes and told me that that is hurting my baby.
What. The. Hell. I am already paranoid enough. But for her to say it the way she did and ROLL HER DAMN EYES at me. Really pissed me off. Will my baby be okay from me laying on my back for the 5 minutes it takes me to wake up in the morning? I hate that I've been doing it. But I WAKE UP THAT WAY. I can't control what I'm doing while I'm sleeping... I didn't know... now I'm always worried about it.