The raw talent and work ethic that is distilled into a med school class is staggering. For many of us, we were the big fish in the pond in undergrad. There will always be someone smarter/willing to work harder than you now. Experience swimming with the sharks. Or you can try to be one if you feel so inclined.
You'll find your priorities, be it grades or otherwise.
Also I find that depth of understanding between grades to really be splitting hairs, minutia that will probably be forgotten, but is tested for the sole purpose of separating the field.