This is actually quite normal. The thing to watch for is what happens after these interactions.
A kitten cries out during play to tell its playmate that the play is too rough. The older cat should then ease up, at least temporarily. (In the excitement of play, it’s easy to get rambunctious again.)
If your kitten continues to want to play with your cat, all is well. If your kitten runs and hides from him, refusing to come out when he’s around, then you need to keep the cats separate for the time being and only allow supervised play for a while.
As for the smothering, unless you have a 20-pounder lying still directly on top of the kitten for a long time, it’s not gonna happen. If the kitten goes quiet the other cat will get bored and get up, and if the kitten gets desperate enough to seriously use all its claws and teeth, the cat’s going to move to go into defensive or fight mode. If your kitten was 3 weeks old I might be worried, but not at 3 months.