This seems more in the area of some type of quantum physics, thing. I don't know to much about it, you will have search the internet, but there is the theory that time only exsist in this reality. And that it is possible to jump into different realities simultaneously. It could be that you are "time jumping" into the future or past. This would also lean heavily on the belief in astral projection. The body can't really physically move through time and space because of it's mass. However, the spirit is a form o pure energy, which would allow astral travel in order to see or even remember these things in it's past or future form. It is also believed that multiple realities exsist and run simultaneously. This would include you living in multiple realities. I don't know if you everwatched the TV show Charmed, but they have an episode when one of the Elder's tries to kill baby Wyatt. The witches don;t know this yet, so they send their unborn son, who came back from the future, back to the future. The elder cast a spell the opened the door the their reality and the dark reality so the "good witches" were switched with the "bad witches", which was their shadow selves and threw off the balance. Because we are both light and dark, in this episode, they portrayed the good side of the witches in one reality and their shadow self living the same life, but opposite in different dimensions. It's hard to explain, but with alot of these quantum type physic theories, they believe in something something similiar, but times 1000. Some even believe that another dimension is created by ever choice we make. Like one dimension if you choose this route, and another if you choose the other route, ect. The only thing seperating it is the veils. It's to big for my brain,lol, but something might looking into. Hopefully,someone more knowledgable in this area will respond with more information and even the correct terminology.
Another theory I have is similiar to the above but revolves more around the present time. It's more about kind of either flip-flopping back and forth into different realities, or you kind of blending both realities together which could be done being really connected to your spiritual self. Alot of people will have to go into a type of trance or meditiative state in order to connect to a spiritual realm. But some people are so connected to their spiritual selves, that trance may not have to be deep at all, simply thinking or looking at something could connect them. It's kind of looking into a crystal ball,, your both here physically, but mentally you wherever the ball shows you. Hmmm, like a daydream. When you daydream, your body is here, but your mind is elsewhere. So, you could be walking "inbetween the veils" and in a sense moving back and forth between realities.
And the last theory is this. Psychic abilities. You could be picking up visions due to the energy you are picking up from the person or thing you are looking at. For example, the bridge, perhaps the designer played around with the idea of how to design it, and your vision could be their memory. Or, perhaps there was another bridge there decades ago and it was the original bridge. Or, you be a pre-cog and are seeing what it will eventually evolve into. This revolves more around the ability to pick up energy and reading it. You can also look into Clairvoyance and see if this may be another ability you have that you are not aware of. Deja'vu's are extremely common for a clairvoyant who if beginning to develeop that ability.
The good news it... You are NOT an MP. (Multiple Personality Disorder). True MP's do have more then one personality, but their personalities are separated and one personality is NOT aware of the other:)
But, yeah, maybe research some of this and see if it fits, and if it doesn't, perhaps it will lead you to another answer. Best of luck to you!