Hurrah for the award! You really deserve it - I think it's amazing how hard you work and how much you put into charitable work.

Don't get too stressed about your work. I think all the suggestions other people have made (about talking things over with your boss, etc) are excellent, but it's important to remembet that we all have 'burnout' periods. It's good to recognise and address them, but it's a natural cycle, so you have to cut yourself a little slack :D