For me feelings are caused in two ways.

One, something happens that incites an emotion quickly without really thinking about it, and there is some or many physical changes. Example: Getting the winning lottery numbers and being told for the first time. I would feel instant elation and joy before even thinking. My body would buzz with happiness, like I was high. I'd feel like I could float of the ground I can imagine, anyway.

Two: thoughts cause feelings, those feelings cause a physical response. This is hard when you have pervasive negative thoughts Because the physical response is, altogether, stress on the body and mental functions, and is constant because of the pervasive negative thoughts. But with normal thoughts you can feel moments of happiness, sadness, etc just by thinking of something that incites that feeling.

For me, feelings are something I sense. They are a sensation within my "being". These sensations can be great, horrible, and all kinds of in-between. They are also obviously accompanied by thoughts of the same nature (great, horrible, etc) and measurable physical responses.. like sweating, fear, racing-heart, sick stomach, etc.

What I "sense" within me when I feel something, I cannot describe. If I'm feeling something, I know the thoughts (or lack of) that I'm having. I know the physical responses I'm having (ex: shakiness). I can describe those thoughts and phsyical reactions easily. Anyone can. But there is some sort of other thing accompanying those that I can "sense" but not describe. It is the most powerful part, though. It is the essence of the feeling itself, I guess. Not everyone feels that way about it, I know.

Yep, I probably just made it more confusing to you.