OOPS!!! GAH! I have been knitting a Gaptastic Cowl for my Sister’s Birthday this coming we

OOPS!!!

GAH! I have been knitting a Gaptastic Cowl for my Sister’s Birthday this coming week, and I have gotten through one and half skeins in the round, when I realize I made a mistake 5 rows down!!!!! Shall I knit on and pretend I didn’t just knit a stitch that I was meant to purl or should I back knit 131 X 4 rows?