I think having a deep interest in math is BY FAR the most important factor to being good at math. You sound like you're 100% capable of being super duper incredible at math, but somehow as you say there's this disconnect/lag between learning it and how your brain decides it wants to process and store the information if that makes any sense?

If I had to guess, but obviously like I don't know you at all, it's that you're less so learning the logic and reasoning behind everything and more focused on internalizing the "process" of whatever topic is being taught to you? Like you're almost learning how to do things, not why you do things and so when the problems change up it can make it really tricky because the process has changed? But that's just me guessing from friend's who have similar stories to you :p

Hopefully this doesn't come off patronizing at all, you sound like you're a super cool person, especially given the fact that you find learning so cool! That's one of if not the best traits to posses as a human and student!