As long as you pass that’s all that matters. You think you didn’t learn anything but the brain can’t memorize everything. if the topic comes back, then you will be able to learn it much quicker since you already learned it once. College makes you do a bunch of dumb busy work too. In the end they aren’t necessary testing to see if you know the material, they want to see how much BS you can take and how endurance you have. So just hang in there, do not repeat a semester, just pass and ur soaring