IM STUCK

At 15yo i did 4 months of bodybuilding then i started having shoulder pain, after that i quit for 2 years and in that 2 year period i tried going back to the gym but my max duration of working out without pain is like 2 weeks, im now 17 and couple of weeks ago i went to a general doctor and he made me do the x-ray picture thing and a blood test, when the results came out he told that i didn't have any problems and that i was overall healthy. And now im stuck here i dont want to ro waste time i want to build as much muscle as possible while im young but i cant workout...