At the very least it is a sprain but possibly a fracture as well. You could start with your primary care physician to get x-rays and an exam. If ortho is needed then you would have to be referred there by your primary care.
If you did not report it right away to your supervisor, things will get sticky with workman's comp. Unless you had a witness, that may help. It all depends on your company policy.
If you regular insurance catches "wind" that this is a workman's comp issue then they may refuse to pay for it or pay for it and then go after workman's comp.
However, you really do need to get an exam, Injuries to the hand/wrist can have a lifelong impact if not treated properly.