How to treat Boxer’s Knuckle

Patient: I’ve been experiencing pain in my middle knuckle after my hand hit the side of a desk and afterwards I began experiencing pain and the symptoms appears that it might be the injury known as “Boxer’s knuckle”. I don’t have health insurance atm and was wondering what I could do to alleviate or treat this problem. I think my tendon ripped apart because I feel it irritating on the sides of my knuckles. Any advice would be much appreciate. Thank you in advance.

Symptoms: sore knuckle, irritation around middle knuckle, inflammation