my protective but loving boyfriend

I wake up in the middle of the night with him waking me up , " bae you was sleeping on your stomach " as I turn over he says " there is a mark on your stomach , that's why I can't sleep at night because I'm worried about how you are sleeping " I'm like babe I'm use to sleeping on my stomach im only 5 weeks .. next thing you know he puts a pillow on both sides so when I turn I just cuddle with the pillow 😂 is it okay to sleep on your stomach while you're 5 weeks ? I guess since we had the 2 MC he don't wanna chance it