Hi, for the past couple of weeks I have been experiencing a dull ache in the left hand side of my chest about three ribs up. It is a tightness feeling, like a weight. Although not 'painful' it is uncomfortable when I sleep and gets particularly more prominent when I lie on my side (both). I am 21, female, thin/average weight. I have also had some recent reoccurring trouble with what I think is thrush, if that is relevant.