Strange burning sensation in my sternum

I am 39 yo female with stage 1 diagnosed 6 years ago. Whithin a past 3-4 days I started to feel pressuse in my chest (around sternum) and I have now burning sensation which starts in the lower part of sternum, then moves up almost to the neck and then goes down again. I don't feel the pressure any more and probably burp more that ususally and have the hot feeling in the throat. I have never had such feeling before. Does it sound like a heartburn? I am not sure because I can not distinguish whether it is behind the sternum, in the sternum or this is skin feeling??? I am so worried. Any idea what it could be???? Thanks!