One way to think about emotion is to understand different emotions like different colors. Just as you can put together a few colors to get many other colors, then you can put together different basic emotions and get many other emotions. That’s how we can say that we have infinity with different emotions.
At the same time, we can ask what basic feelings do we have? This is the controversy though. Some believe that we have 12, some think we have 10, some think we have 5 and some actually mean we don’t have any basic emotion at all. When we work with feelings in therapy, at least these are the basic feelings most common: fear, anger, interest or dedication, joy, disgust, shame, guilt and sadness.
These can be combined into other conditions. For example, fear, anger and sadness can together create the feeling of jealousy. In jealousy you are afraid of what can happen to the loved ones, you are a little angry and want to protect what you have, and you are also sad when you imagine losing the other.
There are very many such compound feelings or emotional states, such as hatred, hopelessness, nostalgia, awe, and bitterness, but these are ultimately made up of these fundamental feelings of fear, anger, interest, joy, shame, disgust, guilt and sadness.
It is not necessarily so important that you know exactly what feeling you know is called. The most important thing is to be able to describe your experience in a way that others can recognize and get what you need when you have it that way.
Do you want to read more about the individual feelings?