People telling me that my body jerks a lot during sleep, is that normal? Does that mean my body isn't resting well?

Myoclonus. I can definitely relate to this. When trying to sleep after studying for a test in medical school, it looked like epilepsy. This is because of a brain that wan't quite shut off yet. Rather than medicinal therapy, try to wind down as much as you can before falling asleep. No computers, TV, internet..etc.