Hello friend,
When we begin meditation, we open ourselves to parts of our brain and consciousness that are normally dormant. Be prepared for things like this, you may experience many different sensations such as stated by Johnson Akemi all of these sensations go with the territory, However they are nothing to be concerned with. Continue your spiritual work and reap the benefits of your hard work. Do not quit, do not give up, sometimes things can seem overwhelming but again this goes with the territory. Ground yourself, and if you feel you need quiet time away from the astral etc. Simply close your chakras temporarily. This can also prevent psychic attacks/vampirism and is also a stage in the magnum opus.
Best Wishes,
Diablo Satanas
HAIL SATAN!!!!!!