Yep... On this website micheal states that astral projection, out of body experiences and lucid dreaming are all the same. Lucid dreaming however is actually what fits micheals description the best and really he just turns astral projection into lucid dreaming by saying that although people think its another dimension it's actually still just in the mind.
I am not here to promote the idea of either astral projection or lucid dreaming. In my opinion nobody should be telling you what your experiences are unless they are just stating what it could be or you don't like to decide for yourself. In the end however it's up to you to decide which theory is real.
For now I'll just tell you a little more about the theory of astral projection since you have an interest in it. The most important thing about it is that there are different dimensions found at different vibrational frequencies. The higher the vibrational frequency the more pure, light, positive and safe the dimension is. The lower it is, the more dangerous, evil and darker environments you will find.
The physical world itself is the dimension you find yourself in now. When you increase the vibrational frequency of your astral body you free yourself from your physical body and will find yourself in either the lower or higher astral dimension. The entities and creatures you find here have either just died or actually live there. It's best you move up to the higher astral dimension otherwise you will be surrounded by evil,deceiving and dangerous entities that will attempt to trick you into letting go of your physical body so that can possess you. In other words you will be left in the astral forever...
There are 7 higher dimensions however than you can explore other than the astral. From memory they go like this:
-----(above this people have different beliefs)
There's also the etheric dimension in between the astral and physical dimension. Etheric dimension entry is often called a "real time" or "etheric" projection. When in this state you can see physical the world as it actually is in real life and if you have enough energy you can partially interact with it or make yourself partially visible to physical people. Overall this is often used as a way to describe ghostly haunting effecting the physical world.
The problem however is that "how do you confirm it's all real and not in your head". People can tell you about these dimensions and you can find them but is your mind just making them from what's being said or are they actually real? What you need to help your beliefs is some personal proof.
For example back in 2009 before I knew about this "it's all in your head theory" I went on an astral projection forum and saw that they had planned to meet up in the astral and play astral tag. I couldn't astral project myself so I got the leader to pull me out of my body and boom... He remembered two things in order that I remembered from the experience without me telling him about them.
He has also told me that entities in the astral are trying to contact me and other people I know. He told me who these entities were but didn't tell the others and just said "look inside yourself and tell me what you see". Interestingly enough he was correct about what each person would see (e.g. God of the mountains for Chris and god of the sea for Daniel). At one point another member from this group I am apart of communicated with the entity connected to Chris (a skeptic) and got it to manipulate the physical electricity flowing through chris's guitar amp to create a bumping sound. It happened only the 3 times she told it to happen and didn't continue to happen once Chris left the guitar amp on without getting the entity to interact with it.
Overall it's up to each individual person to make their own choices about these things so I wish you have a fun and positive journey in the higher dimensions