This is definitely normal. A way of self soothing. They can really get into it sometimes though and it can look concerning, but typically they don’t actually hurt themselves.
Yep. Not all the time, but sometimes before falling asleep.
Yes, my girl used to twirl her index finger into the fabric of her nappy blanket, and my son takes his blanket, balls it up under his head and repeatedly moves and pulls out pieces of the balled up fabric…they all are doing something to self sooth; no worries, it’s a phase…
My son likes when he hits his head on like wood or something. He thinks it’s funny