WAT'S WRONG WID ME???

I have absolutely no idea wat the hell is wrong wid me.... Suddenly I feel so depressed and unhappy... Around my frens, I feel so normal but deep down I noe tat my heart's not at peace.. Its really troubled.. But the prob is, I DUN NOE WAT'S TROUBLING MY HEART?!?!?! Everything started to go down hill when me and dis guy decided tat we were not going to continue being not an official couple... So we decided to be frens but somehow now I dun think we are even frens.. We seldom sms each other, never talk, and even if we do sms it'll be like 1-2 sms... I really dunno wat's happening.. I may be falling into depression.. I feel like everyone's expecting me to do great things.. My exams have just started.. And more pressure to get good grades and not to fail is added to my burden.. I already have so much on my shoulders i feel like already crawling coz of the weight.. I feel really really unhappy deep down... The thought of suicide haunts me... My heart is confused, troubled, unhappy, lost and worried.. Sometimes I really want to give up.. Other times, the burden becomes too great tat I just wanna break down and cry.. Tat has happened to me b4.. I felt so low and so pressured tat I just cracked and broke down. Nothing seems to calm me down.. I really dunno wat's going on wid me.. I'm losing my mind... Pls help me oh Lord.. I need u to help me..