Not Medical Advice: Anecdotal sources suggest that the tattoo was probably not rendered properly; it occurs when the tattoo is rendered too deeply.
It's an indication of infection, so make sure to seek medical advice immediately to clear it up early. If you piddle around hoping it will go away on its own, you may end up with a crater where your ink was supposed to be.
Make sure to consult a different tattooist about your touch-up work.
If you don’t take care of your tattoo then you can risk infection, bubbling, ink fading, and bleeding – not someone that anyone wants to encounter! Since tattoos open up the skin you must remember that your fresh ink is actually an open wound, and treat it accordingly.
Here are some tips on how to avoid a tattoo infection shared by Tattooeasily.com.