Vibrations/sensations vs Emotions

I don’t see how vibrations/sensations in the body can be called emotion.
When I practice processing my feelings, I can name and describe the vibration/emotion but I cannot call it emotion.
For me emotion is when it feels like an emotion. I can’t relate vibrations to be emotion.
How can I really FEEL AN EMOTION because I feel emptiness inside of me where the emotion should be?