unfortunately i'm all too familiar with this topic...
I went through a period of time when I was getting them frequently while trying to stop smoking and drinking and make life changes, i think it was pressure from life and my body reacting to not having alchol, cigs and weed after such a long time of using them....
the only time I get one now is when I'm really hungover, or if i smoke weed...
I still smoke occasionally and i think its because my tolerance to weed has gone done so when i smoke i get really high and it triggers a panic attack..
i have learned to manage them a lot better but they are definately not a fun thing to go through
the best way to describe it for me is I start having hella random, rapid negative thoughts, trouble breathing, feel heart beating, hands tingling, feel like i am going to lose control or go crazy, or just completely pass out...
the best thing to do is get educated on them...
for a while there i couldnt sit in a room with a lot of people cuz i would fear having a panic attack... now i am in school and work with little to no problems and no medication.....
the thing that sucks is fearing having another one, its key to get over that
the only thing to fear, is fear itself
just realize it's only anxiety and its not gonna kill you