My three year old hits, grabs my hair, or tries to scratch my faces when he gets mad at me. Is this normal?

No, No, No dont ask other people to get him for you! You are MOM and need to show him you are in charge and he cant hurt you. When he sees you have other people get him he sees that you are scared of him! You dont want to give him that controll over you. If he only gets that way with you then its probably not something that needs meds to controll. Show him you are bigger than him. When he gets that way pick his butt up and sit him down ( somewhere soft couch) you sit some where else close enough to watch. Ignore all the screaming and throwing him self around get a book so he thinks your reading, dont show him it bothers you....If he gets down you simply put him back and move away as quickly as possible but dont show fear.... try this every time he gets mean! He is just throwing tandrums if it were anything else he would do it to other people too.......Keep saying to him " I am Your Mom You Will NOT treat me this way or you WILL stay on that couch and Never play again. I am MOM I Can Make You Stay There FOREVER!" It sounds mean But You will have an easier time doing it now then when he is a teenager. Plus now you can pick him up and make him sit. Good Luck and be strong!