Large Blisters In Legs, Itchy Rashes. History Of Bad Bite On Leg. No Help From Creams And Antibiotics. Help

Just over 3 wks ago, I got a really bad bite on b ack of leg whilst playing bowls. It got worse and leg went very mauve with a skin thing. It went almost to knee and down to ankle. After a visit to docs. and nurse giving me some cream (oh yes and anti. biots) Within a few hours of applying cream, the affected leg was covered in very large blisters. Didn't use cream again. From then, I was going to surgery every morn to have legs dressed. In the meantime, I am covered in a very itchy rash,sometimes getting up in night to put wet cold flannels over me. I am just on a tablet, like a piriton but doesn't seem to be doing anything. Had rash almost 3 wks now. Thanks.