Thank you for responding!
The thing that's keeping me from switching to Bio immediately is the immense workload I will have to catch up on, as well as the practicals. The calculations for Physics are very easy, but it's coming to those calculations where I have the problem. I can't grasp the concept because I don't think I am naturally inclined for Physics and having such a bad teacher makes it even worse - at least if I had a good teacher I would have a higher chance of understanding, right?
I borrowed the IB Study Guide from our school library, but it doesn't elaborate very much as it's just a study guide. Our school textbooks are pretty bad, it's the one with the green and yellow cover. There are stackloads of those textbooks, because the guy that wrote them taught at our school and ordered a bunch of his own textbooks.
Ugh, I so wish that I could do Physics though - it's the sort of subject where you get that great satisfaction after solving a problem - however I never get that satisfaction, because I never seem to solve the problem! Oh god, I wish I had a better teacher.
I'm leaning towards bio now, the sheer volume of work I have to catch up on is insane but at least I will probably be able to get a higher grade after lots of studying. Physics? I'm not sure I have a chance of survival, I have never felt so completely lost in a subject!