So, I think it all started with a very bad weed experience where I think I experienced a panic attack in one of those small corner stores, started feeling really dizzy, detached from reality, everything was slowed down and eventually, I passed out. Though before passing out I felt like something in my heart had literally popped like a really loud and powerful heartbeat.   
Time has passed since that and here I am a year later watching Netflix and suddenly the same feeling of dizziness came over me. I opened my window to get some fresh air in and somehow managed to calm myself down. The problem is that the feeling of detachment is still somewhat present and I cannot go by my day without questioning everything, whether it is just basic human interaction, the fact that even the words I'm typing in right now somehow describe exactly how I'm feeling, or even how reality itself came into existence.  
If you know the feeling you get in those moments when you look at your hands or at anything at all and for a slight moment that object doesn't make sense to you, that's how I'm feeling, the problem is that it doesn't last for just a moment, but it's been going on for quite some time and I really can't bring myself back to reality.

  
TL: DR Depersonalization that doesn't go away, caused by a bad weed experience