(((Sinatrasbelle))) You sound very overwhelmed. Pre med is tough. Every one who goes through it has had to fight for it. You know you are smart, as you got great grades at your previous schools. Nothing has changed in that department, you are still smart.
Perhaps now it's more difficult, because all of the information coming at you is new. You're basically at ground zero again and once you master this level you can build on it as you did when you first started school as a child.
A school counselor may be able to help you come up with some coping strategies for time management and your class studies, and even hook you up with a study group. There is safety in numbers I always say. The more brains you have studying for a test the better chance you have.
Go easy on yourself. College is a new world for you right now. Be honest with your family as this will relieve a lot of the pressure you're feeling. Breathe...... If you have to repeat a semester then you repeat the semester. Sometimes it take a few times. Be well.