Never head my head with the bar, but one of my lifters hit his head on the Sn which drew soem blood.
I'm fairly robust but training full time Bulgarian style for 11 days took me to pieces. I wasn't injured but I felt seriously beat up and my numbers took a nose dive. My mates numbers stayed strong but his training capacity and stamina is insane.
I've had about 4wrist issues over the past 12yrs. So I've been pretty lucky injury wise but I have a prolapsed L4 which is gash. Means my back is really sore/ stiff in the mornings and hurts a lot.
Just be careful in your warm ups and take care before going crazy on the weights. Make sure flexibility is a non issue for you.