The reason I asked about the last shed is because sometimes after a shed there will be just a bit of blood in the enclosure. Easily noticeable if you use some type of paper substrate (news print, kraft paper, butcher paper, or paper towel). Every time it's happened to me, the source seems to be the vent scale / vent area. My thought was maybe the same thing happened to your guy, but it ended up getting a little bit infected. With another shed coming up, it's something to keep a watch on.
I know in your original post you said you were a new keeper. It sounds like last night you found out the hard way why you should never put any type of tape in your snake's enclosure. They will find it every time, and the results can be really bad.
As for the vent scale, Ill come back and post what the outcome is after he sheds, and hope for the best.
Yea, It wasn't the best idea, but I guess it happens to a lot of people since there is thousands of results on it. I fixed that issue now though! and never again
Shifty
New Brunswick, Canada.
Male Pastel & Female Spider