Its all anxiety dude.. i used to have thoughts like am i really here could this be the matrix lol
think about it this way, people who are having a psychotic episode dont know there are, they believe 100% what is happening to them is real.
the mere fact that you are questioning it tells me its anxiety and that you have a fear of going insane.
stop questioning the thoughts let them be there with no resistance,
the way you feel will be down to depersonalisation (google it and it will explain what it is and will explain why you feel weird)
it is the need to questions the thoughts change the way we feel that makes us worse,]
the best saying i have ever heard is.... you will never get better until you stop trying to get better, "paul david at last a life"
there is loads a pages on web giving advise on anxiety offering treatments for this and that dont listen its a waste of money there is no miracle cure, the only person that can help you get better is you, google anxiety no more that should give you some uselful info.
best of luck