Keep in mind that I'm not saying the results of this test will definitively tell you you're insane. Some of these events could be natural behavior for you, after all, or results of circumstances otherwise beyond your control. It's not supposed to diagnose you, it's just supposed to help you keep a tally on your own mind.
Just covering all the bases here, really. And yes, I realize some are more obvious than others, it's kind of the point.
Answer the following questions with a simple "Yes" or "No". Reasoning doesn't matter. (In all likelihood, trying to justify it might end up hurting your argument more anyway.)
In the past month...
Has anyone else outright called you 'insane', 'crazy', 'creepy', or a similar term for something you did?
--> Would you agree with their assessment in that context?
Have you simply found yourself saying "I know it sounds crazy, but..." or similar phrases?
Have you had an unusual number of nightmares, lucid dreams, or other abnormal REM occurrences?
--> If you weren't prone to it prior to exposure, have you been sleepwalking?
Have you been having what you can only describe as 'visions'?
Have you been receiving unusual sensory input, such as hearing voices/ticking or seeing creatures/figures that nobody else could hear or see?
Have you spoken to yourself in public?
--> Did this draw serious attention from other people?
--> Did this devolve into an argument with yourself?
Have you spoken to inanimate objects?
--> Have you received replies?
Have you found yourself repeating a single phrase at least three times within as many breaths?
Have you found yourself writing in code when it was either ridiculously easy to crack or unnecessary to begin with?
Have you had any violent mood swings?
Have you recently experienced any significant changes in your mood that lasted for an extended period?
--> Could this change be considered positive, contrary to recent experience?
--> Could this change be considered negative?
Have you noticed changes in your own eating behavior?
Have you made any significant changes to your wardrobe or style of dress?
--> Would this include a personalized logo a la comic book superheroes?
--> Do you have (X)perator symbols on every shirt, blouse, jacket, etc?
--> Would this be in a style one would probably only see in Japanese animation?
--> Do your 'casual clothes' include some form of body armor?
Have you recently found yourself unusually bitter towards or paranoid of your close friends and colleagues?
--> Have you seriously wished harm upon them?
Have you found yourself simply paranoid of everyday social interactions?
Have you spent abnormal amounts of time scanning scenery for potential foes while out and about?
Have you believed there was a conspiracy to kill you, someone you know, or an iconic figure?
Have you simply 'felt the presence' of Tall Pale and Faceless, another Fear, or any other supernatural forces/creatures without any other sensory input?
Have you believed you had any abnormal abilities for a human?
--> Have there been witnesses who can confirm use of such abilities?
--> Have you rejected the laws of physics or nature, ignoring damage to the integrity of reality/the universe?
Have you ever believed yourself to be something 'more than human'?
Have you threatened to kill anybody?
--> Multiple times?
--> Was it (exclusively) to deter future harmful action, i.e. "If you touch a hair on his/her head..."?
Have you ACTUALLY killed anybody?
--> Multiple people?
--> Was it (exclusively) self-defense/proper defense of another human?
--> Was it pre-meditated?
--> Were you under the influence of perception-altering drugs, alcohol, 'illusions' or a Fear?
--> Did you simply "go berserk"?
--> Did you do it in the name of a 'higher being'?
--> Did you enjoy it, or otherwise find yourself unapologetic for doing it?
--> Did you cause damages to the body, post-mortem?
--> Did the victim die screaming (or attempting to do so) in what could presumably be agony?
Have you contemplated methods of homicide or harming others, without any particular target in mind?
--> Could such methods be considered 'unusual' or 'creative'?
--> Could such methods be considered 'inhumane'?
Have you simply felt apathetic towards the painful misfortune of others?
Have you delighted in the painful misfortune of others?
While awake, have you had periods of complete unresponsiveness to the physical world?
Have you had extended periods of uncontrollable twitching for no explicable reason?
Have you had extended periods of disorientation or lapsed memory while awake?
--> When you came to your senses, were you ever covered in blood or standing over a body?
Have you indiscriminately considered yourself superior to strangers or colleagues?
--> Have you ever called them your minions, underlings, or other derivatives of servant?
Have you acted like you are, or believed yourself to be under the age that your legal documentation (i.e. birth certificate) says you are?
Have you found yourself singing or humming a song to yourself that was inappropriate for the situation (i.e. a cheery tune while fighting or killing people)?
--> Did you make up the tune?
Have you had periods where you found yourself unable to stop making puns?
Have you had periods of simply wanting to bellow out maniacal laughter?
I think... that's enough for now. If you think of anything else, please do bring it up so I can tack it on for later.
I'm just gonna go sleep and hope I don't end up on the floor of my room again.