random tat scarring

I got my second tattoo about 6 weeks ago (a black band around my forearm) and everything went fine with the healing. Used a reputable shop and an artist that has been highly recommended. The last couple days, the outline of the band has become more and more raised by the day. I called the artist when it started and he said it was probably weather related but wouldnt know without seeing it. Its winter, not humid(thats the trend ive been seeing alot of in terms of problems here on the board) and its just about Xmas so i cant really get to see him any time soon. I am wondering if its scarring or reacting in some way because the outline is significantly rasied but there is no swelling and minor minor tenderness. Any suggestions/thoughts? Many thanks