What Causes Persistent Nausea, Fatigue And Low Appetite Post An Anxiety Attack?

I recently had a panic/anxiety attack. My heart was going crazy. Labs were done and i was told that my potassium was low. They gave me 2 potassium tablets, stablilzed me and sent me on my way. I have been feeling very achy, with nausea, and tired since that episode. My appretite is very low...I am eating but im forcing myself to do so. I am trying to stay hydrated, by drinking gatorade, and water. i have also been eating a banana a day to keep potassium up. my specific question is this. could this be a way that my body is recovering from that panic attack, or is this something else? I have gone to a doctor, well a p.a.; she thinks i have an anxiety issue. i think she may be right....but not about how i feel right now.