Mood swings hyper active. Or is it me?

I feel overly happy and hyper energetic most of the times.My confidence is always at peak while such events and I keep talking and talking then I feel bad for being narcissistic and selfish . I don't feel like sleeping and also I have a bad habit of lying about my personal matters but I was told I'm way too much realistic and it doesn't work this way. I'm very cruel with words when surrounded by people I don't like or if I'm with people who I like or love I'm too emotional. I hate my life anyways my heart rate is so fast while typing this and I want to die. I wonder how everyone is so dumb or is it me? I feel bad for people around me or who care about me and sometimes I feel like they are the luckiest to be around me lol.I'm laughing right now. I think I should kill myself or maybe just simply go to sleep.