Unknown

I'm having unexplained headache lately. It will just come and off.
Though I didn't worry so much, I still made my own diagnosis.
The following are a few of possibilities:

1. I do not have enough sleep.
2. I'm too stress.
3. My short-sighted is getting worse.
4. I do not wear spec when I'm working with my notebook.
5. I think too much.
6. I miss someone.
7. I've bad quality of sleep.
8. I miss home.
9. I'm lack of nutrients.
10. I'm getting OLD!

Conclusion, I have all of the above risk factors that brought me to this condition.

P.S I guess I do too many PBLs in university, which makes me having such logical thinking and linkage between all the things! PBLs rocks!
(PBL- Problem-based learnings)