My 14 week old has been thrashing around all night, constantly waking himself up. I’ve fed, changed, rocked, shushed, etc. Nothing has worked. About half an hour ago I popped him down on his tummy just to see… and he’s been out like a light since. I’m obviously not going to sleep while he’s asleep on his tummy so I can watch him but what do I do if he seems to prefer tummy sleeping? He can’t roll yet although I suspect all the leg slamming is him trying to do that. He’s been an OK sleeper until now so I’m hoping it’s just a phase he’ll move past?