Lower Back Pain Exercises

I've tried everything, from exclusively studying in the library's quiet area, to trying herbals (like gingko) to help me concentrate while studying. For the past 3 years, I've been studying in the same room in my apartment with much success. This year, however, I find my mind wander all the time, especially while I'm trying to read and study before exams -- and it's been showing in my grades. The material this year is much more difficult than the previous years, but it's still managable and very interesting to learn. But, I still find myself reading one page over and over because my mind keeps wandering halfway through.

It's very frustrating, and I would love some study tips from others that have helped them out a lot!