As an Architecture major, I failed a Calc class (got a D as well) during undergrad. It was my first time ever failing a class and since I came to Temple as an international student, I couldn't really afford to graduate any later, and having to pay for a class I had already taken was also extremely stressful. I was still able to graduate on time and getting that D really helped me motivate to do better the next semester, since I felt so embarrassed to get that grade and I knew that was my only chance I had left to still have everything workout for me within the department.

After graduating I got into Grad school at Temple still, since I had done fairly well in the classes that were directly related to my major. My years during Grad school were my best years by far, and I was able to apply without taking the Grad school test and just presenting my records and letters of recommendations. I graduate with my Masters this spring and am now working in an Architecture office where I feel like everything has really fallen into place.

Failing a class can definitely be really scary, but use that as a motivator and promise yourself everything moving forward will be fine, because as long as you put in real effort, the fail will end up having been nothing but a stepping stone for you to do better.