These are not dreams only. The vividness suggests that during the body’s sleep you actually took a little stroll in the lower vital world. In the first dream you simply witnessed a slice of this world while in the other one your consciousness was almost getting dragged into it.
There is always something corresponding to these worlds in human consciousness. Ordinarily these are repressed in the subconscious parts. But there are always triggers such as watching a TV program or simply meeting a person who harbours these tendencies which can open an inner door and then, during sleep when our guards are down, we can slip into these worlds and come in contact with its forces and beings. The good thing is that you were conscious as most persons who enter these dark subconscious or lower vital realms remember nothing when they wake up.
Affectionately,
Alok Da