>>3 I think that's it. It's anxiety that's causing most of these 'side-effects'. In fact, I know a lot of young people nowadays that get tired out easily because of things like academic stress.
I'm not too knowledgeable about this so I may not help much, but here's a few general tips that I think would help:
1) Find the chance to take long walks under the warm sunlight regularly. Why? Because walking is exercise, which can naturally make you feel good. Sunlight exposure is also a natural mood booster, it helps with decreasing anxiety and giving a sense of well-being. You'd also be getting enough Vitamin D to strengthen your bones. :D
2) Have good sleeping habits. It really helps to boost your energy during the day. Also, consuming caffeine is discouraged because it sometimes can increase anxiety.
3) Well, I don't think I need to say much about eating since you sound like you're eating well. But maybe avoiding very spicy foods or foods high in sugar may help.
4) Have at least one or two good friends to always be there for you! Pretty much, just stay in contact with them and confide in them about whatever problems you may feel. Having support from your friends always always helps. :)
By the way, there's also this website that I found to be pretty interesting and helpful. Check it out! It's superbetter.com
I hope you feel better soon, Jessi!