It looks as if you may not have slipped the stitch off all the way on the previous row, and then treated it as a stitch on the next row, therefore increasing. To be honest, I'd leave it.
If you wanted to, you could drop the stitches down to where they increased and pick one up with a crochet hook, but I'm pretty sure you'd have a very loose row all the way up rather than one little glitch that only you will notice.
"Trust the pattern!"
Time flies like an arrow, but fruit flies like a banana.
Hop aboard while we follow the cloud-covered van of knitting harmony, man!! Woooo!! --Hedgehog
IngridKH on Ravelry