Response:

What you  are doing is perfectly fine meditation. When you are coming out of the gap and notice you are not present, that indicates that you have just dropped in the gap. That gap between thoughts is by definition a state of stillness or silence, but lack of clear awareness prevents you from noticing that aspect of it. Still, whether you are fully aware of the experience of the gap or not, you still get the benefit of it.

Love,

Deepak