I have what seems to be a insect bite but it looks like a blister and thats how it looked when it first appeares and itches like mad?

Could be: It is common for some people's bodies to over react to some insect bites. It will usually grow bigger for 2-3 days. As long as it is itching more than tender it isn't likely to be infected. Also if it is just on the one area that was bit it doesn't sound like an allergy, just an exaggerated localized reaction. Ice massage and antihistamines might help.