Is Problem In Bending The Forefinger Post Injury Be Flexor Tendon Injury?

I cut my forefinger two years ago I couldn t bend it for three months but later after trying I could finally do it . Now I play guitar and I have a problem( I can t bend the upper part of my finger I need to push with the other one ) I think it can be a flexor tendon injury and because of it I won t be able to play properly can I be treated now ? Can I do a surgery ? Anything ? : ( please help ! I m depressed