Is there no way to stop it? like right now i'm feeling so depressed and nothing happened! in fact, earlier today i was the happiest i've been for a long time... its kinda starting to piss me off.
you could be depressed or be bipolar or just have anxiety. go to a doctor and they can give you different kinds of personality tests and if you choose so they can give you medicine. you can also see a counselor or someone in that position.