Hello everyone. I have been practicing meditation for a while now and meditate pretty much everyday. Usually when I meditate I get a sense of calmness and peace and heightened awareness to everything that is happening around me. Recently though, while in meditation there are subtle spasms in my back and stomach. has anyone else experienced this before or know what it is? Also when I meditate with my eyes open, the deeper I go into the meditation waves of darkness will begin to flow across my eyes until it is near pitch black. Then the light will return and the cycle will begin again. What is this? Is it normal? Does it have to do wth the meditation or something on the physical level? Thank you.

-Wanders