You'll probably get farther with self-study. I suggest picking a field or two (discrete mathematics, number theory, graph theory, topology, and abstract algebra

You'll probably get farther with self-study. I suggest picking a field or two (discrete mathematics, number theory, graph theory, topology, and abstract algebra are probably the most useful and accessible ones to you right now) and then meeting with a professor a few times a month to go over homework problems. Doing it that way will prepare you to teach yourself the material, giving you the confidence you claim you don't yet have.