If i get straight A;s for the next 3 years can I get into medical school?

I am about to begin my sophomore year in college as a Pre-medicine Biology major. My first year was definitely something to get used to. I confided in the Dean of Mathematics and Science as to what classes I should take for my first year. He suggested that I take biology both semesters and when taking a bio always accompany it with a chemistry and when taking chemistry always have a math. While that all sounded kosher before the year began, when classes started I was in way over my head and felt extremely overwhelmed. My first semester with 17 credit hours yielded a 3.2 gpa. However, because I was taking classes in sequences, I had to continue with bio, chemistry, and math the following spring semester. Consequently, my gpa did not hold up as well as it had the first semester, therefore yielding an even worse 2.8 gpa with an additional 15 credit hours [32 credit hrs total for freshman year]. My school has an academic policy that allows students to repeat a class during fall and spring semesters in which a grade of D,F,or WF was given.The grade from the repeated course will replace that of the first grade merited and not show up on the transcript.I have had an extremely rough time in bio and have gotten a D in the 2nd half of the sequence of my biology classes. My parents are giving me a lot of negative feedback about my grades and for once in my life this is something that I am not used to. I graduated high school with a 3.5 gpa and have had nothing lower than that all of my life. I received a full ride to school on academics because of my hardwork. I am a self-driven student and have been since I was a mere 3 year old in private school [which in the time I learned to read and write in cursive before reaching kindergarten]. Now that I am entering my 2nd year of school as a bio major I am questioning my ability as student to complete this program of study well enough to perform on the MCAT. I know that scoring well on this test is indicative of being accepted into medical school as well as being able to compete with other applicant. I want to continue to do my best and make my parents proud but I want to make sure that this goal is attainable in 3 years. I would like to make sure that I stay on track for a 4 year graduation. Is there any advice you would give or any other options about what I should do in order to ensure a better chance at being accepted into medical school.Should I repeat the bio class?.I have considered the option of an Army Medical Career seeing that my significant other is a soldier and military will become a way of life sooner than later..feedback would be greatly appreciated. Please and Thank You :)