I think it has to do with bipolarity, ocd and maybe multiple personalities. You see, I talk to myself and I DO believe most people talk to themselves but I talk to my ''child'' self, quite often. I can't confirm if that's ''normal'' but I reassure him when he's afraid and but he doesn't answer back so what I do might not be as ''normal'' as I think it is.

XD
Then I have these thoughts where I'll see my friends and say ''I'm happy to see you'' but in my head it says ''you're a fa****!!'' and obviously, I don't truly think that but it makes me laugh a lot and I have to find excuses as to why I was laughing. ^^' When people are charismatic, I tend to think bad things about them even if in reality, I admire them. Or I keep hearing swear words in my head and have to say them, though it's not as worse as before. I might have had tourettes because in my childhood, I had this uncontrollable urge to imitate animals and screaming ''EEEEKKK'' or ''OAAAKKK'' or ''AS*'' very often.
The worst of them all though, is when I see hot girls at the gym and they seems so sweet but I have these really obscene sexual thoughts about doing this or that to them, it freightens me because I'm not like this in real life (I'm shy and very kind) and I don't understand why I'm so psychotic in my head. I'll think about what I'd do, laugh and feel like I'm in control of god know what. I think it's mania but I can't confirm. Maybe it frustrates me to not be able to have relationships because of my shyness so my mind go loose to fill the void. That would make sense, right?