Ahhhhhh, ow. Ow. I'm guessing you can't flex the distal joint in your thumb? Yes, an x-ray is important. If the distal tuft is fractured there's no specific treatment other than for comfort, but if you've fractured into the joint it's a little more involved. You could need a visit to the hand surgeon, depending. So do please follow up. You may need that subungual hematoma trephinated* by tomorrow morning too; relieving the pressure will do a lot to bring your pain level down.
You did this while chipping stone ... please please tell me you were wearing eye protection?
All right, I'll stop being smothery/doctory and hope you get some sleep with the percocet. And keep that thing elevated.
*using a small cauterizing tool to relieve the pressure of a hematoma under a fingernail.