Just Plain Tired...

How does one balance living life to the fullest and doing absolutely everything with resting in each day and slowing down to not miss things in life? I find that hard. I feel like I have so much to do each day but at the same time I long to just slow down and be. I have one life to live. I have no idea how long that life will be. Right now it is just about right at 20 years long. I hope it is long, but more than that, I hope it is full. I'd rather have 20 full years, then 80 empty years. Right now I feel so busy and life feels so hectic. At the same time, I don't want anything cut out. I'm in school, because not only do I love it, but I want the education. I want to be able to teach or do whatever God has for me after I graduate. I'm working with my church's youth group because I love those students. I love getting to mentor them and just walk along side them everyday. I am working because I have to. I enjoy my job and have learned a ton from it, but that is something I must do whether I enjoy it or not. All the things that occupy my time are there for a reason. So why are there times that I just wish life could slow down so I can breathe? I feel like school is going to run me over if I slow down for a minute. I study an average of 15 hours a week (depending on the week), work about 25-28 hours a week, go to class 17 hours a week, and volunteer with the youth for about 6 hours a week. The average adds up to 60 plus hours a week. I just get stuck in this delima of having and wanting to do all those things but desiring more free time. I'm feeling stuck at the moment....and very very tired.