I know the presence of God experience you describe. Overwhelming power of love. Filling to overflow. Peaceful. Powerful. You laugh at any previous doubt. You know it is God. Mine came a month after I told God, "Ok, if you're real, I'll do it your way." I have not been the same after that experience. I instantly knew my life's purpose was to bear witness to the reality of the living God. And I have done so since that fall evening many years ago.