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?
Yes,.. If it's fractured or broken, there isn't a whole lot too be done about it. Dr. might tape it, might not. BUT,.. and this is a big butt, suppose it is
broken. I can't know your level of pain tolerance, but maybe you're a super hero and you get along Ok dealing with the pain thinking it's nothing too serious, so you go boarding again!!
All it would take is a relatively minor bump or fall,.. Now, you risk having a jagged shard of rib shoved into a lung or worse.
Really better to be safe than sorry!! K?
If you have insurance I wouldn't hesitate. If you don't I'd still get it checked but that is just me. Plus I'm old things heal slower and I break more easily
...and here I was thinking "I" was the only one that gravity was treating differently than it did a decade or two ago??