Red spot around the outside one day after tattoo?

Hey guys,

I got my first tattoo yesterday afternoon, so I'm not sure what it's like. I've done three small, fine-line tattoos.

The tattoo was then covered with this foil and I took it off that same evening on the advice of my tattoo artist.

Two of the three tattoos now have a red "square" around the outside, exactly where the foil is stuck. As far as I know, I don't have a plaster allergy because my tattoo artist asked me about it before applying the foil.

I thought maybe it was from the tattoo cream I use on the tattoos, but it's a straight pattern, just like the foil is stuck on. Could this be redness from peeling it off? It's been a day since I removed the foil.