It may be hard for you to believe this but i specifically created this account just to respond to your post.
I had the same problem with Anatomy. I was battling the fact that there was so much memorizing to do and I didn't take my studies serious until after my second mid-term exam. It was like some scales suddenly fell off my eyes!! I was on a D just like you with one more mid-term (exam and practicals) and a few homeworks left. I went to discuss with my professor and he was diplomatic about telling me what to do but I sensed from his words and expressions that he was doubtful of my ability to pass the class. My niece who is a nurse encouraged me to finish the class that I could still make it. I hate failing at ANYTHING i commit myself to so I knew dropping as far as I was concerned, meant I had failed, hence, i made up my mind to WIN. I ate, slept, drank, walked and talked Anatomy from that day. I listened to Anatomy lectures on YouTube when driving to and from work (I was working two jobs by the way), in the gym, while taking walks. Mind you I generally do not enjoy studying but I loved Anatomy by force and thanks to God, I ended the class with a strong B!!
My point is to let you know that passing Anatomy even with your current D is not impossible. It will be very difficult, it may disorganize your life temporarily, but, it is not impossible. The question is ARE YOU READY? Answer this question genuinely. If you're ready to give it 150% from today, then don't drop it but if you have doubts, you may consider dropping it. Only you can genuinely answer this question. Its all in your hands and if you make up your mind to, sincerely, then you will. Best of luck to you!!