Bumps on tattoo

[Import84]

I've had a tattoo on the outside of my lower arm from elbow to wrist for around 3-4 years and just within the last 2 months I also ended up with 4 bumps ranging from the size of a bb to a pea. They are only on the tattoo. Its  only black ink. They have started to slightly hurt and burn if I apply pressure and the skin just around those bumps have gotten a bit red to. The skin on top of the bumps is flaking or shedding. I have had tattoo bumping in the past on both of my tattoos but I fixed that by changing to aveno scent and dye free ever since my first tattoo about 5 years ago.