Glad it was only a few stitches that you needed and not a replacement thumb (we can't do without our thumbs). Hope you heal quickly.
Rotary cutters should be changed a lot more often than most of us change them. I've been buying the Harbor Freight Tools rotary cutters and at $1.00 each you can afford to change them a lot more often.
With the lady that almost stuck the seam ripper in her eye and now this with the rotary cutter, it is a great reminder that we work with extremely dangerous tools and need to be very careful with them. I know that sometimes I get distracted and have had a few near misses myself. It is always such a sobering feeling when it happens.
Take care...