I appreciate your realistic evaluation of your own achievement thus far, and the rigor (or possible lack thereof) of your high school curriculum. And yes, being an AA applicant DID boost your application. You might not have been admitted, had you not been AA. You are right to be concerned.
Over thirty years ago, I knew a young man, AA, who had been admitted from a low-level college to arguably the best med school in the country. The school supported him in every possible way, but when he just couldn’t learn the material, he finally had to drop out, with lots of debt. It was really sad - he would have made a good doctor, I think, but should have gone to a least competitive med school, with a significant AA student population, where I think he could have made it through.
All that being said, YOU ARE WRONG TO DOUBT YOURSELF!!! Even though you didn’t get 1600 SATs, 1510 is nothing to scoff at. And a bunch of 4s on the APs is also nothing to scoff at. Most importantly, you work very hard for what you get. This is a GOOD thing - you will be a hard and steady worker through college, and you will get through. A friend of mine with four kids, said of her least bright, but hardest working kid, “Give me a hundred like that one, as opposed to my lazy brilliant ones.” And it’s true- that one is at an Ivy, doing extremely well, even though they’re the least bright of the kids.
Prepare yourself by reaching out even before you get there to every student academic support/tutoring organization there is on campus. Also reach out to AA student support groups - you won’t be the only one arriving who might not be the best prepared, and you will all help each other.
You CAN do it, and what’s more, given your previous track record of achievement, you WILL do it!!!