How much is the psat score for this?

Using the conversion table in the Prep Booklet from this year, you would get a 75 in Math, a 73 in Critical Reading, and a 66 in Writing, for a Selection Index of 214. Your score likely won't be exactly that, as each test is a little different, but in that general area if you actually missed what you think you did. (That's also uming that you left none blank and just got them wrong, though you would only improve by about four points if you left all of them blank instead of answering incorrectly) Commended definitely, maybe Semifinalist if you live in one of the states that is on the lower end for qualifying scores.