Hi LolaMD,
Calculus is essential to a complete understanding of medicine. At the most basic level, the diffusion equation describes the movement of molecules down their concentration gradients. A growing trend in medical research is the use of computers to calculate, based upon simulations, the appropriate medicinal dosage rather than having to carry out costly laboratory experiments.
Moreover, as a doctor you will use tools built upon calculus knowledge. Though you may hate it, the most revolutionary advances in medical technology use much more math than calculus.
I advise you to take a deep breath, study some, and really try to see the utility of calculus in your future career as a doctor. Although you won't be sitting there solving equations, you
will have a deeper understanding of the technology and physics that you will be using to improve the lives of patients.
P.S. Here's a link to an article on my website about enzyme kinetics and calculus:
http://eigensheep.bio.uci.edu/?p=75