If your pattern is this one that I found:
ow 1: Knit. Row 2: Purl.
Row 3: Knit 1, *purl 1, knit 1. Repeat from * across.
Row 4: Purl.
Repeat for pattern.
You probably added or missed or added a knit or purl row at the point where the pattern reverses.
You can take it off your needles, rip out until a row before you need to be, and then pop out one stitch at a time and slip each back on the needle.
When you're working stockinette, which this is, except for row 3, the V's should be facing you when you're knitting and the bumps will be facing you when you're purling.