Fluttering inbetween heart and throat

Sorry ladies forgot to add this to my post re painful joints also getting like a fluttering sensation above heart and below throat - almost like the beginning of a panic attack or an adrenalin (sp) rush only last seconds but unnerving. Becomming more consistent as treatment goes on. (Been on Herceptine, Arimidex, Zoledex since Jan this year). Anybody else experienced this?

Thanks again