No one can do better than 99th percentile. Your parents know that there is no such thing as 100th percentile, right? Your perfect SSAT score is not what will keep you from being admitted.
But once you’re admitted, chances are you won’t be the smartest kid in your class. What will your parents say when your grades turn out to be mostly high Bs no matter how hard you try? And how will YOU feel about that? These are the important questions to ask yourself and discuss with your parents in the next few months. The combo of unchecked parental ambitions and a pressure-cooker school is way more concerning than a couple of missed SSAT questions.