To me it looks like a spider bite especially if that bite spot in the center seems to hollow itself out.
However, I agree with Crux that you should go to the doctor for a medical evaluation.
Hi Christian, aw, thanks for your good wishes. Doc reckoned it was a bullseye, and prescribed three weeks of doxy. I've had lyme before, and am very down to face to it again, given what a torturous journey I've had with the first infection. I have swollen joints, hives, lethargy and nausea so there's clearly something going on. Not sure when is best to test, or even really how long I should take abs for at this point - or if doxy is the best one to take. But am too brain fogged to think clearly.
That's a helpful shot, thank you! I did see a doctor, who reckoned it was a bullseye, and prescribed three weeks of doxy. I also have symptoms that certainly are reminiscent of lyme, which I first contracted ten years ago.