Red rashes in Thighs, hands, back.

I had mutton two days back and suddenly after 2hrs I got red rashes on my body like in hands, Chest, Thighs. I went to a general physician doctor nearby and he has given me Avil injection and tablets like Allegra 120MG, Ataraxia 10MG, Okacet Cetirizine. Red rashes went after 2hrs and I was fine. But, still next day morning again the red rashes came. On second day, I went to other doctor(since I went on a trip), she has given me Anti-allergic Injection, Praiscort E ointment and tablets like 1AL Levo Cetirizine, her local tablets. After 2hrs the red rashes have gone. On third day morning(14th May), again the red rashes came all over my body. No fever or no other symptoms observed. The same type of problem I faced in 2008 after having mutton and same red rashes came. Kindly suggest me that, 1. General physician or Dermatologist? Which doctor have to consult for my problem? 2. Normally how many days these rashes will be there? 3. Kindly suggest treatment for me.