Wow, you lead an extremely busy life! I can imagine it is hard to find time for exercising and good food when there is so little time left. I was wondering how you manage your eating usually? Do you cook for yourself, or do you eat much fast food? Even in fast food there are better and worse choices, it would be good to be informed about those. The exercising during breaks that you do sounds like a very good idea. You could also try if a fitness video works for you, for example Jillian Michaels' 30 day shred (a lot of the people on this board are following that one). You can do it in your room, you don't need any special equipment except for some weights (can also be water bottles, large candles, milk bottles etc), it takes only about 30 minutes. You can even do it in the mornings or just before you go to bed.
It also sounds like maybe you just have to much to do. You write that you are "constantly stressed". That is not good! It isn't very healthy in the long term either. If I were you I'd very seriously look at everything that takes up time, and try to find something that you can quit. You need some time to take care of yourself, you are important! Exercise and health are also appointments, not something last on the list. Good luck
