Taking a step back would be a great idea. Higher level math is very visual..not only on paper but, also visualizing concepts in your head. If math is part of your program and a skill you had before part of the aversion might simply be that what was easy is now difficult. Is it a skill you can recover? Others here would have a better idea. I am new here and my husband is the one with the concussion. If it is, taking a step back until your brain has healed more might help you enjoy it again.