I have a weird growth under my collarbone it shows mostly when I push my chest out. Both my collarbones crack time to time and iv mostly felt pain or stiffness in my shoulders mostly when I wake up. I m scared it might be a tumor .. It doesn t move isn t soft but not hard either. There s no pain on my collarbone. It s seemed to be growing ang getting worse but I must add my posture is not the best. If I hold both my arms out and swing them back and forth one direction it locks up I can feel weird movement the other makes pop sounds. That s the are with the bump on the collarbone the other arm only pops if I swing forward and grab with the othe and pull down. I also notice that one collarbone looks like its sticking out on top of my shoulder. If there s any email I could reach you at to send you pictures that be great there s no pain once I get up and move around though. But if I sit down or lean I get very stiff.