How much more stressful is college on a non-traditional student, and what are some good ways to deal with college stress at 30?

What can I do to get some support after an act of violence happened on-campus at my school (or off-campus, but to a student here)? I feel a little lost right now...

I've never been very good at managing my time, getting homework done, or staying organized. Yet, I learned to work around this and get things done rather successfully. However, recently, I haven't been able to do ANYTHING. I can't get school work done. It's starting to impact my grades. I think this might be a result of a stressful junior year combined with a stressful summer job. I worked 50 hours a week at an understaffed Boys and Girls Club. There might be something about taking care of children — many with serious family/home issues — that really drained me. I only had about a week of summer vacation where I wasn't either working or at home with pneumonia. I went from a rough summer into a difficult senior year. Now, I feel like I need a break to collect myself, but I know I won't get that break until I graduate. What can I do? I don't think I need new organizational strategies, I've picked those up over the years, but then again if I knew what I needed I guess I wouldn't be asking!

Does exercise really reduce stress? I recently took a new job that is very high stress, and I need a release. My friend says I should take up mountain biking, that it will reduce my stress (and keep me from gaining weight at this desk job). Thanks for the great site.