Given that you have had persistent pain with a limited range of motion, as well as continued swelling of the joint 2 weeks after the initial injury, it is strongly recommended that you seek out a consultation with your primary care physician
for further evaluation. It is certainly possible that you may have suffered a fracture (broken bone) involving the thumb, which may or may not extend into the joint space. This joint is particularly prone to such injuries given its exposed position and its use in such activities as the one you described.
There are also 2 main supporting ligaments that support the joint that is causing you pain; these are the ulnar and radial collateral ligaments. A history of trauma to the thumb in the setting of sports play is a very common story seen in damage to these ligaments.
Given the importance of the thumb in maintaining fine dexterity and performing complicated motions including gripping, it is very important to address thumb injuries in a timely manner. Your primary care doctor
can start an initial work-up with x-rays to rule out a fracture. You will also likely need a referral to an orthopedic hand specialist for further evaluation, as many of these injuries will require surgery
and/or splinting to heal correctly.