This might sound odd, so apologies.
Lately I've gone through what I would probably describe as a mildly transformative time in terms of 'spiritual' awakening - but for no particular reason I can pinpoint. As an agnostic who has generally veered towards atheism it's been very odd to experience this pared-down, simple realisation of a sense something at the core of all the nothingness. Anyway.
For no particular reason other than the notion just came to me, I did some reading about how to mediate, settled on the principles of mindfulness meditation, and this morning I did a sitting meditation which has left me feeling vaguely freaked out.
Within a very short time of focusing on my breath and simply observing my thoughts, I came to a rippling dark void behind my eyes where even the fairly loud burble of my children playing in another room dimmed away. I had to pull myself away after maybe 5 (? I don't know) minutes here in this place of utter stillness and emptiness and I had tears streaming down my cheeks although I didn't feel sad, simply like I had finally got here after a lifetime away. I was woozy for a few minutes and couldn't quite 'come round'.
The point of this rambling tale is: how could I have not known this empty place of peace existed, and how could I get into such an altered state on my first 'try'? Am I deluding myself? I typed 'void + meditation' into google afterwards but a whole load of very odd stuff came up, including some satanic blogs 
Please, someone help. I have no idea what I'm even asking. Just... is this 'normal' for meditation?