Anxiety

I have frequent anxiety attacks. Sometimes I can pinpoint a cause, other times I can't. Just recently I had one from playing a game. In the game I have to throw barrels to hit a target which is alot harder than it sounds. What would have once just pissed me off now has my heart racing, has me feeling naucious, and has me feeling a sense of dread I guess. My mental health has gone to shit the last month or so, it was always bad but now its worse. For the last year I've had stomach problems which the doctor hasn't found a physical cause for, I even had an endoschopy and they said everything looks normal. I'm starting to think It's a physical symptom of my anxiety. I'd be grateful for any advice this fine community can offer. Thank you.