I'm having this issue but on my upper leg to the upper thigh area. All the redness has spread a good 3 inches and it's been about 53 hours since the tattoo was done, so a little over two days now. The redness just seems to be getting worse all of a sudden now, but it is a very large piece.
The actual swelling is going down but this redness suddenly struck and just grew outwards like wildfire over the last 2 hours or so, it's reaching towards the back of the inside of my leg. It isn't on both sides of the tattoo, only the inner side of this tattoo. The rest of the tattoo just shows signs of initial redness around the linework. (This is a colour tattoo, not just black with shading alone).
I don't know if I should be worried or not, it's been a while since I got any tattoo and this was a cover up job that's still a WIP.
I don't even know if anyone will read thus but it's really worrying. The work was only a near straight 6.5 hour session.