Pain in the front of your shoulder may be a proximal (close to the torso) bicep tendon issue. If you feel pain when pushing open doors, picking up heavy items or doing press-ups/bench press in the gym then it may well be the biceps tendon. This is an injury that I have seen a lot recently, it appears to be common in younger more physically active people. While the more notorious shoulder problem of rotator cuff tears are more common in more elderly people. Anyway, if you currently have anterior shoulder pain then keep reading for an exercise that I have seen help many people recently get rid of their pain.
Typically, when we think of strengthening out biceps we think about flexing the elbow, while this is working the bicep it is only half of its job. The other half being to flex the shoulder (raise the arm forward). And from my experience people often injury this part of the bicep through shoulder movements such as lifting heavy boxes, bench press, press ups, racket sports, truly anything that places high amounts of stress on the shoulder.
It may not be the bicep that is the culprit with anterior (front) shoulder pain, but if it is, the following exercise, which focuses on the proximal part of the biceps should help you to strengthen the damaged tissue and get you back to normality ASAP!
Flex elbow to 90ish degrees and flex shoulder to 90ish degrees
Slowly extend the shoulder keeping elbow flexed at 90ish degrees
Keep extending down until your upper arm is by your side and that is 1 rep done.