Newby - question on pattern

I am making a sock - I have 64 stitches divided onto 4 needles - 16 each needle. Here is the pattern: K1, sl 1 pwise, K1, yo, psso K and yo, k1… repeat. When I finish the row I have 18 stitches on the row. Is the k1 at the beginning of the pattern and the K1 at the end of the pattern the same stitch? In other words, do you knit two in a row? Should there be more stitches at the end of the row? I guess my question is this: should there be 16 stitches when I finish knitting the row?

I assume you mean 16 stitches on each of the needles, not the row.

It depends on the rest of the pattern. Sometimes a lace pattern depends on how many rows are needed for the pattern repeat. If you work the first row you may have more than the original 16 stitches on each needle but after you have completed all the rows needed for one pattern repeat you should have the same number of stitches as you started with.