REG issues

alright so ever since the maintence last week (i think last tuesday) my reg has been totally off, its taking 8 bullets to the chest to get a kill with an m4 5 or 6 to the chest with an ak and even sometimes 2 to the head and i really have never had this issue till last week. i have re-installed cf already and idk wht else to do. it has only been since last week where its started doing this so again i really have no idea wht to do. soon im not gonna have a comp because im gonna rage and break this damn thing. so PLEASE I NEED HELP WITH THIS