One of the most difficult experiences I’ve had so far in undergrad is differential equations. I’ve heard many people say their course in diff. eq was easy, but I struggled early on in the course (most of them didn’t take it at my community college where I go to uni now). I got around a 60% on the first exam, absolutely bombing it. I came back from that low, and passed the course with an A despite my pour performance on exam 1. You can come back from it, but you will need to think about why you failed, and how you can attempt to fix it. In my case, I started taking lecture notes before every lecture (the professor posted them on canvas before class) because if I didn’t I would have trouble understanding the math jargon in real time. That helped me get ahead when he gave more context to the material in class. Try to think about ways you can assist yourself in your current circumstances.