always best to get things checked out, my dh ended up having 2 months off work last year after some nasty tick bites, he had never reacted to anything before and the docs never did prove what was wrong with him, but we were lucky as I insisted he got a second opinion after being turned away by one doc even though the rash was huge and he felt awful- the second one put him on antibiotics straight away.
He's fine now but we always tuck our socks in our trousers when walking now!