There are five primary emotions: fear, anger, joy, sadness, and lust. There are many other emotions which are not considered to be primary emotions, and a primary emotion is not more intense or more important than any other emotion. The emotions are primary in the sense that all other emotions are either a variation of them (think of the numerous shades of a primary color) or consist of a mix of two or more primary emotions experienced simultaneously. For example, as mentioned above, anxiety and panic are lighter and darker shades, respectively, of the primary emotion fear. Similarly, frustration and rage are lighter and darker shades, respectively, of the primary emotion anger. Familial love, by contrast, is a mix of sympathy (which is a shade of sadness) and joy. And romantic love, the king of all emotions, is a cocktail of exuberance (a shade of joy), lust, longing (a shade of sadness), with just a dash of anxiety (a shade of fear) to keep things interesting. Part of what makes romantic love such a powerful experience is that involves the activation of so many (four out of the five) primary emotions all at the same time.
Some emotions are the product of physiological changes which take place in the chest cavity, some are primarily in the upper back, shoulders, neck, and jaws, some are primarily felt in the abdomen, and some emotions, like the startle response involve powerful physiological responses throughout the body. Variations of emotion are practically endless and, ultimately, are subjective. For the purposes of this blog, the point I am trying to make is that emotions are physiological changes which are attended by body sensations, and that these changes take place not as acts of reason or will, but automatically, unconsciously, from the parts of the brain collectively called the limbic system, and are carried out by the ANS which is not under conscious control. Emotions are much more about physiology than they are about psychology.