Pain in left breast

Hi all after some advice, I’m 37, I’ve had a dull ache/pain on the top of my left breast for about 8 months, it mainly hurts when I get up in the morning or if I’ve been sitting down watching the tv. It doesn’t hurt when I’m working or moving around mostly. My gp examined me and suspects muscle strain (I lift weights), I am waiting for chest x-ray results. When I press down on the area it’s tender. It’s on the flat part of my breast, which could be the pectoral area. I know some say pain isn’t a symptom, but sometimes can be, I’m a worrier! Dr said to take ibruprofen for 2 weeks, been taking it for a week now and no change. 
also comparing the feel of it to my right breast isn’t exactly the same, is breast tissue symmetrical? 

Sorry you have this worry . Breasts are not symmetrical - I think most people have one bigger than the other and slightly different shapes - it’s when things obviously change in terms of appearance that there could be concerns . It’s good your GP has examined you and it sounds like a you a sensible explanation for your pain - hopefully an X-ray will re-assure you .x