Swelling of feet and hands symptoms and conditions

Recently I was prescribed bactrim for a staph infection. On the fourth day I developed a severe rash all over my body. Swelling of my feet and hands. By the time I got to the Dr. my blood pressure had dropped dangerously low and I nearly fainted. The Dr. gave me three shots, cortisone, prednisone and one other I cant remember. By that time my breathing was weak. So the Doctor sent me by ambulance to ER.During the five minute ride my pressure dropped really low again. The EMT started an IV. SInce Primary care Dr. had already taken steps to treat me, ER did very little other than keep watch of vital sighns and let IV finish. ER Dr. concluded it was do to bactrim. He prescribed prednisone and over the counter benadryl and sent me home. After taking prednisone rash seemed to get worse, noticed new rash behind ears and on the top of my head were lumps. Blood pressure has been spuradic at best, but not dangerous. It has been 24 hours now and no changes. My side effects include headache, backache, swelling of feet and hands, rash all over body, itching, raised welps on legs,arms,behind ears and on top of head. The swelling of my feet has went down but my hands are still swollen and sore to the touch. One question. There seems not to be much medicine to help this. I just have to let it run its course how long could the recovery take.