spiderdust

I've had this tattoo since 1996. Never had any problems with it. Suddenly today, it feels itchy and sore, and the sun part feels raised. Not the area around the sun, but the actual outline. However, it doesn't look red or anything, and it doesn't even appear to be raised (at least not to the naked eye). I can't figure out what's going on.
Could I be reacting to the ink now?? After 6 years?? This tattoo goes the whole way around my ankle, and this is the only spot that's bugging me. I don't shave my legs very often, so it's not razor burn, nor does it seem to be an ingrown hair problem. I haven't been wearing socks lately, and I've been wearing shorts a lot, so it doesn't seem like something could have rubbed it and irritated it.

Any clues?