Last Saturday a cat walked into my apartment and wouldn't leave. He was clean, seemed well fed, and had a collar on, so I assumed he belonged to someone in my complex. I took him to the vet and he is not microchipped, posted him on several lost pet boards in the area, etc. I am still actively trying to find his owners and holding onto him in the meantime. He has not left my apartment or been around any other animals since last Saturday; when he first came in, there were no visible scars/wounds/etc. on his body that I caught. He just hopped up on my bed and I saw this wound behind his ear:
He does not seem to be in pain and is not acting strange. The only vet in my area only has an open appointment next Monday (which I scheduled). I do not know any of his history.
Is this a bad wound? What should I do? Can I clean it - if so, how?
This is my first time having anything like this happen to an animal around me, so I'm sorry for being clueless. Thank you for any assistance.