Kind of a stupid question but need opinions

so im a FTM and many mommies love laying on their bellies i've read questions of moms asking up until when can they lay on their bellies and the comments said " until you can't anymore " or until you have a big bump well with me im 29 weeks with a small belly and I still lay on my belly although it starts hurting sometimes . 
If it hurts me am I hurting my baby ?? 
sorry if it's a stupid question i'm just curious .
btw when it hurts i'll stop laying on it and I sleep on my side it's just during the day that I lay on my belly