If the problem in the photo is a yarn over that was knit into then there will be an extra stitch. Do you have more stitches now than before? Another possibility is that you accidentally slipped the stitch instead of knitting it. If that's what happened you can just drop the stitch above it off the needle, run them down to the slipped stitch and pull the yarn through that stitch with a crochet hook and then do the same for the ones above. I've done that more than a few times.
Do you mean that when you picked up the work again you went the wrong way? That will leave a hole I don't think it looks like that's what happened.