It's just practice man, don't worry too much. When you get to mcat prep, just study hard, do lots of practice exams, and you'll be fine.
For context I am a naturally good test taker. 2300 something on the SAT and 523+ on the MCAT, but the MCAT score came from practice, the SAT did not. I took a practice exam before I started content review to get a baseline and was at a 511 with huge content gaps, so natural test taking ability and logical reasoning (pulling answers from the texts) is a big part of the exam. Im not discounting that, but you can improve that stuff and content gaps with lots of practice. My last 4 full lengths before taking the exam were 525+ so I was confident going in and that's how you become a comfortable test taker. If you only do 2 practice exams and maybe one of them is where you want, you're going to have doubt when you go into the real thing, but if you put in the work and get the scores where you want consistently beforehand then test day is the easy part. You just have to trust the work is done and show off what you know. That kind of mindset is why top athletes win and that's how anyone can kill the mcat. Not everyone can get a 528 but everyone can improve their score immensely with proper practice