Contractions?

I’ve been having contractions the past few days but they keep stopping eventually. I tried to lay down to take a nap and I had the absolute worst pain of my life. This was no round ligaments pain. It felt like someone was giving me a c section with no meds. All I could do was lay there and scream into my pillow no matter how I moved it felt like hell and even worse when the baby moved. Has anyone else experienced this? I’m waiting a few minutes to see if it happens again. I’m 38weeks