dolphin 01,
Like you, I suffered from panic and anxiety attacks for some time and was taking medication.
If the problem has worsened of late, it could be that you may need to consider meds as a short term help for your condition.
I was attuned to Reiki in the middle of all these problems and found it to be a tremendous help. I experienced no issues following my first and subsequent attunements and my Reiki Master put this down to my having practiced T'ai Chi for many years - my body was accustomed to handling the energy.
I would advise you to give yourself self-Reiki regularly and to put your plans to take Reiki 2 on hold for the time being - I feel you will instinctively know when you are ready.
Might I also suggest you consider taking up T'ai Chi or Chi Kung. The mindfulness required by the form and exercises will have a wonderfully calming yet energising effect( if that doesn't sound too contradictory.)
Once learned, the Yang Long Form, for example, takes roughly 15 minutes from start to finish and if you can put that small amount of time aside daily, the benefits can be quite startling, particularly in stress or anxiety related situations.
Good luck and take care
Brian