1. Watching him/her walking away and doubting while you're still in the game.
2. In any competition, facing the truth that you are rejected for the others are better than you. (Yet, awesome only when you can tell yourself: let's forget and move one and work harder.)
3. Seeing your you-still-love one posting sweet couple photos on Facebook or Instagram.
4. Wanting to do some certain things but you cannot just because your ego say no.
5. Having too much work to do in very limited time.
6. Being unable to speak your thoughts out.
7. Knowing that your best friends cheating on you.
8. Finding out you're no longer matter in someone's life who you still think about.
9. You're far away and physically impossible and your parent(s) is now ailing sick.
10. Seeing others better than you and they are looking down on you.
11. People judging you, using their won yardsticks and not even bothering to remember that each person is uniquely gifted.
12. Walking in a group in which you don't feel any belonging sense.
13. When your stomach moans and you still have to sit in class.
14. Seeing your close friends checking in or posting happy photos on Facebook and you are not even informed of the get-together.
15. "Seen but no reply" message on Facebook.
16. Not having enough time for your family.
17. Not being able to go home for a family lunch on a Saturday. That really sucks.
18. Not telling her/him you're into him/her and years later finding out that s/he was into you too. Assumption kills, really.
19. Losing a loved one.
20. Your teacher punishing you and not the others for the same mistakes you both did.