Help. Hot water bottle on belly freak out.

Deni
Has anyone who's had a healthy baby before used a hot water bottle on their belly? I fell asleep with one on my chest a few days ago and when I woke up an hour later it was on my belly and really warm. I wasn't hot myself, just my belly area. I've read some comforting articles that it can't hurt the baby but I'm still freaked out and looking for some reassurance.