I'm getting off pill, been on it for over 13 years. What can II expect as far as side effects?

Just depends. You could simply resume your previous cycle pattern, you may have a delay in beginning your next cycle or you could have more cramping or bleeding. Often it will take a few months to know what you "normal" pattern will be.
Minimal. When you stop contraceptive medications, your cycles will return like they were before starting them. Usually the cycles are heavier and can be more painful without the pills. Otherwise, there should be no side effect.