Possible heat spots??

Hey guys I'm stumped here, found this spot on my boy, it looks like raw skin is just a little circle. He's an indoor cat - it looks painful and I'm not sure if it's been growing or not it's very new.

I tried to take a picture but it's not showing anything helpful

A couple days ago I bought a new litter.. This is the only thing that's changed.

Any thoughts are appreciated!!

We really need a photo

Like I said the picture doesn't show much, but it is more red and raw then the picture shows... also his fur around it was slightly matted which  seemed like it was from blood? It's just this one spot and its in the middle of his shoulder blades