2 weeks ago I had my timing belt changed and a new oil pump seal put in. Today the end of my balance shaft broke off or came off. Would the balance shaft being broken have anything to do with when the mechanic put a new timing belt and new oil pump seal in?

 

holy crap what!?!

you're balance shaft broke? yeah it needs to go back the the mechanic that did the work. he was all in there messing with balancer belts and what not, in order to do a T-belt and seal. more than likely a bolt just came loose, but the guy that did the work needs to be the one to fix it.

any mechanic that cared about his reputation would offer you discounted or free work in the future. just FYI.