For a freshman just getting used to the system, you're doing fine. Your GPA can get up to a 3.7 if you get straight As all of next year. Calc II is not a prerequisite at 99% of med schools, and there are worse grades than a B-, so don't worry about it. Take your coursework seriously and good things will happen to your cGPA over the years, making you competitive in the application process when the time comes.