Which size are you making? Doing a gauge swatch will help u to end up with the same size sweater that the designer did. Everyone knits differently. So 3 different people can use the exact same yarn and needle size but end up with 3 different sized sweaters! That's why it's so important to do a swatch and compare what u get with what the designer did. U don't want to end up with a sweater 40" wide and 50" long!!!!! Sorry to say, but I would recommend going back and doing one.
For your other question, after u bind off the stitches you either knit or purl the rest of the sts in that row. Depending on which row you're doing.