Why do I go to bed and wake up with scars and scratch marks on my body?
I get itchy at night, too. Maybe you should try taking some Benadryl before you go to sleep.
There are too many reasons to really provide all the possible answers to this question. Best solution I can offer is record yourself sleeping a cheap camera and memory card will do the trick just don't need top quality recording just to see whats going on and if it might be something to cause concern. As far as lighting get a night light that produces green light it won't disturb your sleep and just do some experimenting with the camera so you put it in a place that provides enough light so the camera can pick you up in the dark. might need an extension cord to bring it close enough. Typical reasons for this something in the bed is scratching you up could be something as simple as stray plastic or beads. Your scratching yourself. This could be a result of sleep issues, health issues or a bug problem. (though bug problems would typically leave bites which would be obvious) anyways best of luck
ask the tiger over there in the corner of your bedroom .............................