Waking up nauseous

Hello Ladies,

First trimester, I had on and off nausea but had no problem sleeping. It stopped around week 12 and now at week 19 I wake up in the middle of the night feeling nauseous. Once i am up, if i sit up the feeling goes away but as soon as as i lay down i feel like i am going to puke again.

I have had no heart burn or upset stomach during the day leading up to this. Even before pregnancy i didn't have heart burn or acid reflux issues.

Anyone else having these symptoms? Any recommendations on how to stop it?