Red mark on foot for several weeks

Can anyone tell what this is? I've had if for several weeks. At first i didn't think much of it, however after a Google search I've now scared myself into going to make a GP appointment after the weekend.

It isn't raised, or itchy.

Can anyone tell what this is? I've had if for several weeks. At first i didn't think much of it, however after a Google search I've now scared myself into going to make a GP appointment after the weekend.

It isn't raised, or itchy.