This is just my opinion.
Don't be a jerk. Yeah, someone tried to correct you, so what they are wrong, doesn't help anyone by flipping out, which leads to my second point, the pot just called the kettle black (or however it goes). Yeah real smooth, considering your gpa you don't have the right to call anyone an idiot for making mistakes. Oh by the way medicine is your life? Really? 1st semester undergrad and medicine is your life?
Also, your class schedule is easily manageable. Yes I did read the part about the family issues. Since you are an "aspiring surgeon", and assuming you turn your gpa around blah blah blah what are you going to tell the patients family if you screw up? Oh stuff is bad at home so I botched the surgery. Maybe your situation is pretty bad, maybe not but learn to compartmentalize a little bit.
I can say this because I was the same way for a while, now I didn't screw up my gpa but I had the same attitude. Take all your classes seriously, no matter how trivial it may seem. For biology, for most colleges it's just memorization. Chemistry, do practice problems, a lot of practice problems. A good way for me to know if I actually know the material is that I go on MIT's OCW website and if the course matches up I'll take the practice exam. So far, if I can get through one of their exams, I'll make an A on what ever test I have.
I wish you luck next semester.