First of all, kudos for actually going to the supermarket. A lot of people try to avoid it with anxiety.
Also try and focus on these bold parts for a second. You're on a journey of discovery right now. Congratulate yourself for staying off the booze, it's a big deal and 100% the right decision. And no, it absolutely won't disappear overnight, it never does, ever. Panic attacks will still happen for now, but I bet you're able to recover from them more quickly now and not catastrophise them into a pit of negative inevitability. Be annoyed, be frustrated, but absolutely don't be disappointed with yourself, definitely use it as a re-learning tool, find out what's making you tick.
What I used to do in situations like that (I would force myself to go to the supermarket daily) is when the panic attack happened, I just sat with it inside the supermarket. Very rarely I would have to leave and go to my car, but once I came down a bit I'd go back in again to finish my shop. Exposing yourself to this panic is not dangerous, and using what you've learned with meditation and positive thinking by talking yourself down whilst it's happening can be part of the recovery process. Even if you get 5% relief while it's happening, it is an absolute win. Remember, during a panic attack your sympathetic nervous system is trying to tell you you're about to die. If you can take control of ANY of that, you're doing really well. Adrenaline is rocket fuel, and is very hard to fight against.
Frustration is inevitable at this point in your recovery because as far as I can tell you can already see light at the end of the tunnel, and that's almost worse than having no hope at all sometimes as you know there's further to go still!
You will get there.