Dear Time Traveler, you have stumbled upon the conundrum of predestination.
If every event is predestined, do you really have free will?
We're not sure, but our lawyers have informed us that it's not our problem.
Or, if you're feeling particularly masochistic, you could try Free Will Fallacy Faux Pas, where we'll pretend that you're in charge of your own destiny, just for kicks.