Let's get back to the problem you had, what the Drs described as a panic attack. Whenever I have felt panic there has always been some or several underlying problem even tho I learned some relaxing techniques to get through it. It wasn't uncommon for me to feel short of breath and very anxious at the same time.
Undiagnosed health conditions such as gluten sensitivity (Celiac Disease and non-celiac sprue.) People with intestinal problems often become congested with gallstones.
You were inhaling some pollutant or toxin that caused constriction of you pulmonary system. This happens to me whenever I'm in heavy traffic or smog. After the exposure I cough up clear mucus.
The Liver-Flush may have released toxin producing enteric bacteria into the intestine. Anxiety is one response to these toxins.
This may have been a sign that your body had become too acid instead of slightly alkaline. I use diet to keep in blalnce. See acid and alkaline forming foods.
Perhaps you were so excited when you were describing the successful Liver-Flush that you were hyperventelating.