Contractions when I’m sleeping/laying down

38 weeks today and I just woke (1am) up due to the most awful cramps that radiates sharp pains from my back. They came every few minutes and I finally decided to get up and get my phone and now they’ve stopped. I’m afraid to lay back down! I just want to sleep 😫😫😫 I have an appt this morning at 8:45. Any suggestions on what I should do? A warm bath and some water perhaps?