Youtube has a lot of good math tutorials that have cleared up a lot of concepts for me too.

I think you're right about the anxiety thing. When I get anxious on test day, and even in class, and even at home doing math (I have major math anxiety) I start skipping steps and flipping positives to negatives and taking shortcuts that don't make sense and taking steps that don't make logical sense just out of sheer panic that i need to get it done NOW, and then I end up screwing myself over.