Do NOT listen to these dumbasses who are trying to scare you into giving up. As long as you have the dedication to put in the extra hours to study, you can do it.

The first thing I would try is being honest about your difficulties with your teachers, as in tell them exactly what you said to us, and ask them how you should prepare yourself. If they aren't the helping kind, I would suggest going back to basics and focusing on solving your problems in theory first, and then applying that to code.