I Have Difficulty Breathing And Have Been To The ER

I have difficulty breathing and have been to the ER a couple times where it was treated with a nebulizer. The conditions come on with swelling in my abdomen and edema that has been getting worse. The itching all over my skin is to the point where I break the skin. At the ER they took an X ray, ECG, and I had an ultrasound. No indication of heart problem by structure or function. I was given HCTZ, 25mg, but that does not get me through the day and, to be frank, have self-medicated by doubling the dose. The salt pills to make breathing easier. The itching will raise in small bumps, but an allergist says these are not properly welts and not the result of an allergy. My family doctor is unavailable for the next week, so I am going to a walk-in clinic in a couple hours. What are intelligent, helpful questions to ask him/her? What should I know or be prepared to hear?