You haven’t gotten many responses so I thought that I would give my opinion.
I think that what you have experienced is normal in any class that might be thought of as a “premed” class. First year biology is of course one such class. I have heard multiple cases of exams where the class average is in the 40’s (and I saw at least one such exam in graduate school, but definitely not in a premed class). Both of my daughters witnessed similar exams in their first course that happened to overlap with classes that premed students were taking.
These are tough classes intentionally.
I think that it would be a good idea to talk to the professor. More importantly, learn from this experience and understand what you are going to do differently next time. When you talk to your professor, the emphasis should be on what you are going to do better next time. You might want to talk about how to pace yourself for the next exam.
This will definitely not keep you out of medical school. Your reaction to this might be one major thing that will either keep you on track for medical school or not.