assuming you didn't damage a lung or break multiple ribs.
And the only way to know that is to go see a doctor.
To be fair, Cr0 is probably right and it's probably just a broken rib and there's nothing to do but wait.
But why take the chance?
To quote the sticky:
It's not a place for you to get a diagnosis of your injury. If you are asking that question, you might as well go see a witch doctor. Better yet, go see a doctor.