SAT test plan does this sound fine?

I took the PSAT/NMSQT in my sopre year and got a 150 on it. I am now planning to take the SAT in the Fall of my junior year (which is coming up soon) and I will take it again in the Spring of the same school year. I just want to take the SAT early to see the difficulty and if I don't like my score I will study and take it once more in my senior year.