How to tell if i Broke my finger! need to know?

so i was doing a double back handspring on my friends tramp. on the second one i hurt my pinky finger really bad. it got worse and worse the knuckle is purple, and underneath the finger it is swollen, it overlaps my other finger more than it should or ever has, the pain has moved also under my finger and into my hand, should i see a Doctor? do you think it is broken or jammed or sprained? It is hurting fairly bad :'((((((((