Really need a bit of help with this one as not sure what to do. DS is 4 1/2 months and has just started to roll to his side and front but can't roll back. For the last week he's managed to roll on to his side in his sleep and will now only settle if put his side in his cot. The issue I have is last night, I should add after an awful day of no naps the movement monitor went off at 1am and I found ds on his front. He didn't even stir when the alarm went off and only woke up after a few seconds of me holding him, was all a bit scary but everyone keeps telling me it was probably a false alarm. My instinct tells me it wasn't and that he was so tired and in such a deep sleep he rolled onto his front and I think stopped breathing but I can't be sure. Anyway as above he will only sleep in his cot if placed on his side, I know he can do his by himself but if we place him on his back he just gets annoyed and won't sleep to do it, if that makes sense? My DH says we should just put him to sleep on his side and leave the monitor on.
What does everyone think? I'm so torn and worrying that he'll do the same tonight!!
Sorry for the long post but really could use some rational thoughts/help