So I had a small insect bite come up on my leg 2-3 weeks ago that was initially a small red bump, didn't think anything of it and didn't see what bit me. I had been walking in the woods after it appeared. But over the last week or so it has gone flat and turned into a bullseye. Still fairly small about 2cm wide but a fair bit bigger than the original bite. Does this sound like a tick bite? Do I need to see a Doctor about it?