Just sad or depressed?

It sounds to me like you are dealing with rejection. Not in the actual sense that you have actually been face-to-face rejected, but as in you may have felt like you were rejected in the past because you didn't fit in, or the friends you did have didn't understand you. Either way crying is good for you, but constant crying may need attention, because it may mean depression, or deep anxiety, or even both. No matter what people say depression and anxiety do not have to last forever, there are ways of getting through it. You are still young, a youth group/group therapy would be good for you if you feel this problem is ongoing. Remember though, do not give up, you must be strong if you are willing to ask for help, because it shows your courage. You seem very smart, keep your head up, don't be afraid to cry, but remember to much of anything is a bad thing. Good luck. =)