Hi, I'm a 19 year old female who's always been healthy. Recently, I've been having an ongoing, deep, burning sort of ache in my upper back (sort of between my shoulder blades) and in the upper part of my chest (right along my sternum, clavicles, and shoulders). I can breathe fine and I don't seem fatigued or anything. It's just this constant sort of pain. I was wondering if it could be a symptom of anything serious or if I just have a slight infection or cold. I'm not coughing, congested, or otherwise sickly, but I haven't experienced this before either. Could you let me know what you think? Thank you!