I think it's one of those things we will never understand. How did it feel like before being born, before the body even existed? How will it feel like after death? Yes, your brain is what gives you feelings and all that, just like a the parts of a computer make it do what it does. The difference with being live beings is we have a consciousness, self awareness, freewill, etc. We could lose our sight, touch, smell, hearing etc... but still have consciousness even though you really have no clue what's going on.
There are lot of things in this world we are simply incapable of understanding fully. They are not accessible to us. I think the easiest way to put it is let's say there are 2D creatures in a 3D world, these creatures are inside a 3D box that is opened on one end facing out along the Z axis. They cannot go there as they only exist on one Z point and only have X Y to go on. Basically they are inside a square, not a box, because this box extends beyond their realm. This square represents our universe. We can go all over it physically given the proper technology, but we simply cannot go beyond that. When we die and before we were born, we were/are not physically there. Where, I don't know. Nobody does.