Adding unwanted stitches in stockinette help needed

[ellenvictoria]

Hi, My name is Ellen. I have been knitting for almost a year now and have not had any problems working stockinette stitch until now. I am currently working on a new cardigan. I did a long tail cast on of 120 stitches and worked the first 5 inches in garter stitch, no problems. Changed my needle size to size 8 and began working in stockinette stitch and have knitted approximately 23 inches into it. Well I counted back my rows and noticed that I had 124 stitches instead of 120. I assume that I was doing yarn overs and ripped it back. After working on it, I had only 119 stitches. I continued working with the intention of increasing a stitch on the end. Well after working a number of rows and being diligent not to carry the yarn over the needle and keeping it in back, I'm back up to 122 stitches. I am at a loss of what I could I am doing wrong and am truly frustrated. Does anyone have any ideas as to what I could possibly doing wrong? Any help is greatly appreciated. Sorry so wordy. Ellen Victoria PS. now I have two extra loops on the end.

[salmonmac]

You may be adding extra sts at the beginning of the row. When you turn after a knit row, be sure to pull the working yarn down from the needle. If you pull the working yarn up from the needle, you'll see what looks like 2sts but is actually only one. If you knit those sts, you'll be adding in an extra stitch eac