So to preface I have a history of anxiety and panic attacks mostly during my teen years. My anxiety now is now mostly manageable. 

The last couple weeks I been dealing with this weird emotional restlessness. I have felt this before, but just on a few instances. I will try and explain. 

Example I can think of. Feeling I had once when I was visiting family in another country. I befriended some people there and had a great time. The night before leaving I knew this would be over and felt this deep emotional feeling that this is all over and I would have this heavy feeling wash over me. with this sort of restlessness where It would be heavy on the chest feeling occasionally make me take a deep breath. 

I'm having something like this again, but for almost no reason. I have to walk and walk for a good 2-3 hours a day to try to tire myself to somewhat quell this. Even music I hear in a store may amplify this sort of feeling. I don't know if anybody can relate to this? 

Is there a name for this?