may you shoot off of the wall if you haven't already used your two hit wall limit
I will assume you are refering to shooting off of the wall with the 5-man rod, since that is the rod of possesion where the rule applies. You may shoot "off the wall" . Assuming that "off the wall" means a bank shot originating from the 5-man rod.
The rules state:
23.2 A player cannot make the ball strike the side walls of the table (or the side strips if present) more than twice before passing or shooting from the five-man rod. Regardless of which wall the ball touches, a total of two times is all that is allowed
prior to advancing the ball. If the ball goes to the wall a third time, it may not be struck again by any player figure on the passing rod.
Therefore as long as the ball is being advanced (ie a shot or pass) then using the wall for a bank shot would be legal.
Pat R