If I remember correctly, you can look at the questions and ascertain which ones you missed. Generally, for the better students, they can also discern why they missed it.............didn't understand the type of problem well, tripped up by working too fast, computation error, etc.
I think finding how many were computation errors can help raise your confidence and settle you down to getting a good score. You just have to keep practicing and get used to working under pressure. Resist the temptation to "grind" through each problem if you get stuck, and, in fact, I think you can argue for skipping lots of problems and then coming back to the ones that look harder.
Use the test paper for scratch work so that if you actually finish early, you are ABLE to double check your prior work Quickly, rather than doing it all over from scratch. The key, in my opinion, is to maximize the correct solutions to the problems you feel comfortable with, and acheive them accurately and Rapidly. Speed in doing the ones you DO know creates time to check for errors and time to noodle over the more puzzling ones. Try a few tests under extra time pressure by cutting the time by 10 minutes or so. See how you feel about that.
Keep in mind too that for those in less than the super accelerated math, you are likely to improve substantially with the passage of time as you do more math in school.