It would help if I could see a photo, but what I think it means is this:
You have 44 stiches joined in the round. If you place a marker at the start of your round, when it says "knit back and fourth for 12 rows" what I think it means is that you should knit 44 stitches (to your marker) and then turn the work and purl 44 stitches (to your marker) 6 times. If you do it this way you should only get one thumb hole, between the 44th and 1st stitch. I presume the pattern will then have you re-join in the round for the rest of the hand.
What you need to remember is that when you're purling your way back, your needles will be on the far side, hope that makes sense. If you know how, it might be easier to knit backwards.