I have been having a strange feeling in the center of my back...spine about chest high. there is no pain or tingly feeling, just a strange feeling that i can notice that is hard to explain. its not a big deal during the day, but when i lay down to sleep it is noticeable and hard to not think about. when i stretch that part of my back or crack it, i get a weird feeling in my chest and it makes me cough sometimes. there is also a bubbly feeling that occurs in my chest often.. almost like a small pop you get when you start to burp on purpose. i do not experience any pain unless i run.. then it feels like someone is stabbing me in the chest. also, sometimes when i take a deep breath it feels like i was just swimming and it makes me cough. any help would be appreciated. thank you!