Is it normal to feel completely detatched from the world around you?

Recently, I've realized i get these random periods of time (can't really pinpoint how long) where I feel completely detatched and withdrawn from the world, almost like i'm watching my surroundings like a movie, during these times I tend to have numbness to almost any emotion (even though most of the time I am what many people would describe as very enthusiastic), I don't interact with people or things around me, I feel an almost hollow feeling like there's a barrier between me and the world, and I tend to not remember many details of what i've done once I snap out of it. The most recent time this happened, I actually almost overdosed on my daily medication though i can find no logical reason why i would do so. Also, if i didn't start to feel the strong effects from them, i would have assumed I just imagined it, it feels so surreal in retrospect. I am honestly starting to fear that the next time this happens, i won't snap out in time to stop myself.