I second this. Having studied to the postgrad level, I've come to appreciate just how broad the subject is. Looking back, I feel it would have been near impossible for me (personally) to get here without the help of lecturers and tutors - often prerequisite knowledge creeps in unexpectedly, and you come to rely on them to guide you through this.
I agree also that regular grading and a lesson schedule help to both push you to learn, and for you to assess your progress in an unbiassed fashion.
Personally, though, I am biassed - and am thrilled when people say they want to learn more maths. I love maths, and find it very rewarding. The best of luck with your journey!
*edit Android version 9