How do you get yourself calm again when your freaking out?

I get so angry that I could kill and it scares me. Im so angry at the moment and don’t know how to deal with it. Im physically exhausted from it and if it wasn’t for this sleeping pill Id be screaming in rage still. Im so sick of being like this and its cost me so much in life already. Im exhausted and stressed and angry and idk how much more I can take.