I am experiencing hand pain and hand swelling after hitting my thumb in a contact sport however their is not visible bruising?

Injury: Even without bruising, you have sustained injury to that part of your body. If the problem persists for more than a couple of weeks or worsens, consult your doctor. In the meanwhile, try NSAIDs and ice .

Injury: Hand injuries are tricky. With swelling of the thumb and pain the require evaluation even without bruising

Be seen: You could have a serious hand injury, for example a fracture of the navicular bone, and have no bruising whatsoever. I would not hesitate to be seen and thoroughly evaluated.