The Doctor Did A ECG On Me And They Said

The doctor did a ECG on me and they said it came back ali5le difrent from my other ones so they kept me over night and did 3 ck and it came back normal and I got a echo of the heart and astress test and it came back normal I'm still having a little bit of chest discomfort it come and go away it started from my back then all my blood work came back normal now long am I going to feel this discomfort?