infected tattoo

I've had my 1st tattoo for about 4-5 weeks and i have broken out into a rash. I've gone to my doctors and they are not sure what caused it. Does anyone know anything about tattoos being connected to something like this? I've tried to research it myself and have came up with is granuloma which is a skin infection from being injured during the tattoo procress. Does anyone have any other ideas or how to possible get rid of it? Thanks guys!!