i cant say i´m experienced at all, but i also worried about that and i constantly placed my hand to feel his breathing.......... and i didnt liked the idea of him sleeping on his back, in case he threw up i didnt wanted his to broncoaspirate so i rather have him sleep face down and facing sideways.......

but whatever works for you better.........i also had this nightmares where all sort of bad things happened to him, i stil do but less often, and i think its pretty normal to be that way since you dont want anything bad to happen to them and you....like think ahead what could go wrong so you can prevent it......so dont feel weird i´m just like you