None of us have even experienced the full range of what humans can experience, so even we don't fully know what it is like to be any given person, we only know what it is like to be ourselves. It is kind of amazing when you think about it.
Andy Weir's The Egg makes regular HackerNews appearances.
Of course it could all be claptrap that humans want to believe in but I find it to be pretty powerful and I think it is true
(Warning: Gets into spiritual stuff)
I sometimes wonder about this, too. Do other people perceive things like I do? If someone was magically transplanted to my body, would they scream in pain "ooooh, this hurts, how could he stand it", whereas I consider the variety of discomforts of my body just that, discomforts? And similarly, were I magically transported to another person's body, would I be awestruck by how they see the world, how they perceive the color blue (to give an example), etc?
Have you never thought you remembered something with clarity, only to be told it's impossible because it never happened? Or another example, I often vividly remember something from a book (it was a photograph on this side of the page, lower right corner) and then when I look it up, it was in a different location and it wasn't the photo I remembered. But my mental imagery felt so precise!
I'm with grandparent, I think I would perceive my younger self as simultaneously familiar and alien.
Yeah another example I think about from time to time is our own sense of perspective. It's all relative, but my sense of how far away is "that thing over there" is probably different from yours. Partially because we may be different sizes and heights, but also because our eyes and brains process the world differently. Like a camera with different lenses.
Also, speed. If your brain's clock is faster than mine then you may perceive the world to be moving slower than I do.
An interior designer will see the colors, and the layout and how the things go together or don't. I don't see that, and in turn the designer does not see what I see.
So never mind the physical senses, even on a mental level two people do not see/experience the world the same way.
Pain, like vision, resides in the brain; like vision it is mostly determined by reports from our (non-brain) nervous system, but pain, light flashes, even objects and people can be created whole-cloth by the brain itself. And "real" inputs can be ignored, like a mild pain you're desensitized to, or the gorilla walking amongst the ball-passers in that video.