Whatever you are feeling, or not feeling, right now is all part of your healing process. it is not unusual to be unsure how to process your emotions. Your best friend physically attacking you most likely inspires a plethora of contradictory emotions which require a certain amount of processing. Feeling nothing is a defnense mechanism against this internal onslaught. How you proceed from here will have a lot to do with affecting your capacity to work through all of this and heal.
I hope he fulfills his promises, but if I were you I would come up with a plan regarding what to do if he does not. It is up to you if you want to talk to him about it, but you need to get yourself to a safe place. You were okay this time, but what about the next? If he can resort to physical violence once, he can resort to it again.