A random tattoo question

Most of the time when I tell people this they think it’s my imagination. But I swear it’s not. So I want to know if anyone else with tattoos has experienced this:

Sometimes when my feet get really cold my tattoo on my foot hurts. Not my whole foot, just the tattoo. The skin feels really tight and it almost feels like it’s throbbing a little, I think?

Occasionally after I got it touched up last summer, my turtle on my lower back would hurt the same way. It doesn’t seem to be doing that anymore, though.

None of my other tattoos do this, just my foot and used to be my lower back.

Am I nuts? Imagining it?