Baby moving 180 during the night

Ok ladies so 3-4 times now my baby has wiggles or rolled or something during the night to turn himself 180. He’s still on his back but his head is on the opposite side from where I laid him. My LO is almost 5m on the 20th and moves around like crazy in his crib in his nursery. He sleeps great in there and we love it. The first time this happened I had to ask my husband if he got up during the night with our LO and put him back in there wrong but he says no every time. Well it’s happened about 4 times now. Anyone else’s baby do? Also with him moving around so much in his crib how do I keep him safe from hitting his head? What do you ladies use? Of course I’m worried about bumpers because of suffocation but I’m worried with him being so mobile at night.