For past 3-4 weeks I have been feeling down. I don't like to eat too much i'm always thinking about things that has nothing to do with the work I am doing. Sometimes out of nowhere my heartbeats starts going really fast I get trouble breathing my body starts to get hot and it's hard to come back to normal what is wrong with me as soon as I start thinking about my personal things I get this fast heart beats and weird sensation that I can't shake it off.