What is this? Odd reaction to a bite?

[Spottyspottyladybird]

Around a week ago I noticed itching on my leg and now I have this. Anyone have any idea what it could be? It looks like a bit in the middle but I can’t remember being bitten. It seems to have some blisters in it?? :s

It COULD be a tick bite. Google bulls eye rash. If so, it's crucial you get antibiotics within two weeks of the bite. This will prevent you developing Lyme disease, which you really don't want. Get to GP asap!