When meditation is "going well" it can be the sweetest experience. When it is not, it can be so frustrating. So mind-boggling, so much like sitting in the midst of a whirlwind.
To me the sweetness of dhyana is marked by the silence I encounter. It's a silence that really is not silence. There is the beating of my own heart I hear. That gentle buzz of the slight tinnitus I've had my entire life. But nothing else. I hear no other sounds that are present. I can focus my gaze on my third eye but all I see is nothing-ness.
And yet there is everything. The hand of God is resting lightly on my shoulder, letting me know of His (yes. sorry. His) presence. Letting me know He is here. And if I I rest in His presence then I'll be able to hear His small whispers of love and care.
My experiences in that kind of dhyana are fleeting. Only seconds at a time. But they are so sweet that they bring me back to my cushion over and over so that I can experience it again and again. Hoping always that I can lengthen the experience.
How do you know you have been successful in dhyana? The yogis say "You are successful if you sat. Nothing more."