“Is this ringworm, mrsa or spider bite?”

I thought I got a spider bite behind my ear then was told by a friend it looked like I scratched it. Later at my overnight shift as a patient care tech, on a floor where I have patients who have many condition some requiring contact precautions mrsa, mdro, vre, c diff, I asked my supervisor if it was a perfect circle since it itched and might have become ringworm, which he replied it was close to a perfect circle but the borders were/are not risen. I decided to treat it like I used to treat ringworm when I have gotten it, spraying tinactin antifungal foot spray on it which it felt like it was burning (how it used to feel when I sprayed and got rid of some back in the day, unless I used fluconazole) although now it is very red around it and I have pain all around my ear/back of head causing headache and looks like there is an additional pimple looking thing above it.