Why do I get these weird feelings, psychosis?

Sometimes...random times I believe that someone, or more then one people are watching me and that life is just a test and there are scientist like, testing how we react to things. Sometimes I think and alien is going to abducted me and night and I never go to sleep...and I will wait till morning to sleep. Also there are times where I talk to myself, about things.... and say out loud "Why are you even still here, you are worth nothing, just kill yourself." And then I say "NO! Don't think that" Or something, and it goes on and on....and with that I get this strange feeling to urge things... I have urges to say things that make no sense or move very quickly almost making me look like I have turrets but not quite. I also believe I seen things, but I can't really tell if it was real or not and It makes me confused. My head is confused, I don't know what to do... I'm 14.