Unless the cream had bacteria in it, it can't cause an infection. The infection has to come from someplace. On the other hand, the artist wiped the cream off, a layer of skin came off with it, and they tattooed you anyway? That's really irresponsible, if you are describing what happened accurately. I'd find a new artist and quit using numbing cream. It looks like some sort of allergic reaction to the cream, but I'm not a doctor.
Tattoos hurt. I'm old school, but I think you should earn your tattoo. I've got hundreds of hours in the chair, lots of very sensitive parts tattooed and I've never used numbing cream.