Tendonitis costochondritis fibromyalgia

So for over 2 years now on and off I've been experiencing terrible shoulder pain & tenderness...My doc say it was tendonitis...Started medication and for a short time it helped..Then I started experiencing tenderness & pain on the left side near the ribs so my doc said costochondritis & prescribed steroids which cleared it up...Now I have the shoulder problem back plus tenderness & pain in my chest which the doc says fibromyalgia....I also suffer with Acid Reflux...This is so confusing for me as the doc never refers me for xray etc just says what he thinks...Does anyone suffer with any of these conditions?? Can you shed some light plus give some tips to help please?