As the title of this thread says: what universe are we meant to believe Miles was/is inhabiting?
First let's assume that the universe that Miles lives in at the very start is our universe (i.e. everything inside this fictional world is identical to ours -- ok other than spiderman being a real thing, but you get my point). Normally, this is what we'd simply assume at the start of most movies and this should be no exception.
But during the film there are two prominent things that deviate from our norm. There's the fact that Dr. Octopus is a woman, instead of a guy, and more interestingly that the NYPD is called "PDNY" twice... At least that's what I thought I heard.
So are the filmmakers telling us that Miles' universe isn't ours, as his reality is ever so slightly different? Or is this the effect of there being a glitch in the universe after he returns to inspect the spider that bit him? Maybe after the reactor explodes and the parallel universe spiderpeople enter into his? Because these deviations only seem to start after these events at the beginning of the movie.
But I'm pretty certain that by the middle of the film Miles isn't in 'our' universe, irrespective of whether it was like that at the start or occurred after those events. (And if the latter is true I wonder if he traveled back to his original universe at the end.)
But since Miles never notices these changes I'm guessing that it was like this all along? The "PDNY" is and always was his reality? In that case I find it a rather interesting idea as it highlights the fact that Miles' universe, and to a lesser extent himself, isn't anything special/unique and the film itself just so happens to be showing us a glimpse of his life by pure random choice. I understand how meta this sounds, but the film is stuffed with these references. And before you think that I'm downplaying Miles' importance -- I'm not. I'm only using this theory to underline the key concept that anyone from anywhere can be a hero if they want to. By acting like a random kid from a random (parallel) universe can move past his insecurities, embrace his responsibilities and become a hero, means that we, in our own universe, can do the same and it's just a matter of time before our spiderman does the same.
Origin comic slams onto table