some times these feelings are from things that happen to us, sometimes they are from a malfunction of the brain. there are skills to help you cope with having the feelings, and not letting them rule you.

there is a post in the PTSD forum , on Anxiety Management Skills that might be of interest to you~ it's kind of dated, so you might have to use the Search Bar to find it~

i hope you find a way to get free of those feelings,, they diminish life so much~'

best wishes~
Gus