Some of my dreams are so lifelike that it feels like I am traveling to another dimension. There have been times that people from my past reappear in my dreams so I can resolve an issue-but they often will appear in the wrong place at the wrong time. I have also thought of going back in time to change the past but that goes against my life theory things happen for a reason.

I have been lucid dreaming for over 50 years, I don't have nightmares and can adjust me dreams taking them where I want.
I taught myself this because of a reoccurring nightmare.
There is nothing magical about it at all nor can you leave the confines of your brain but, that being said, your mind is a big place with near endless possibilities. You can't time travel but you can relive and change the past and see where that goes. You can imagine a million possible futures testing each one.
I highly recommend it to anyone it will change you view point on the world and teach you to see the wonder of the real world.

I have an open mind about this sort of thing. But just like the " Near Death Experience " phenomena, there is simply no way to definitively determine that it is not just a hallucination.

What is this a quote from? I've never had control over my dreams like this, except a few times when I knew I was dreaming but it's difficult for me to maintain focus in a dream, as things tend to blur. But I don't think dreams hint at or connect us to other realities (e.g., other galaxies or parallel universe). But I do think dreams and daydreams provide us with a creative outlet, to build forms in the clouds of our minds.