A great Hungarian mathematician named Polya once famously declared,

"If a problem is too hard, it is because there is an easier problem you have not yet found. Find it and solve it."

Whether or not it is the subject for you, Mathematics is incredibly useful and need no longer be a struggle. The difference between low exam results and a high level of achievement is in fact a comparatively small step in comprehension, and is very often a simple case of approaching problems from different angles until you find one that clicks for you. Each idea you come to understand will inevitably help you to understand the next one, and so a mathematical mountain can soon become a mathematical molehill just by taking things a step at a time. As with all achievements, a certain amount of practice is required, and the best advice I can suggest is to test out your newly acquired knowledge with examples once we’ve clarified the principles.