What is the anatomy of an emotion? First, you experience the emotion. Nothing makes sense in that moment. You're just dripping in whatever chemicals soaked you because your body and mind responded to a thing that happened. You just sit with this emotion for a while, probably a little lost as to how you got there.
And then you enter a new stage, hopefully, where to acknowledge that what you're experiencing is an emotion. You sort of grab hold of it and lift it up and say, "Hey, I see you. You're an emotion." You're still experiencing the emotion, but at the same time you've realized that it is a thing. And there's a decent chance you're a little less lost as to what happened.
In the next stage, you move from discovering that you've experienced an emotion, to determining or estimating the nature of the emotion. For example, "Oh, I'm afraid!" or "Oh, I'm sad!" You still don't really know why, but you've started to name it and now it's taking shape in your mind. It might take a minute to determine whether you're sad, mad, afraid, anxious, embarrassed or whatever. And it might be a combination of one or more other emotions.
After you mostly come to terms with the emotions you're experiencing as far as what they're called, then you need to do some work to figure out why you're experiencing these emotions. This can be a bit tricky, but if you're deliberate about it, you can get fairly close to the source. In complex situations, it might be that you were triggered and got hammered from a residual well-worn emotion from your past. In less complex situations, it is just the thing that happened a few seconds ago.
Once these steps are completed, then you might need some time to sit and think through what just happened and step through the anatomy of these emotions. In most cases, it's not simple like this, but what I've described is the skeleton of the process. It may take a few minutes to do this work or it make take months, or even years. The key is to practice and follow repeatable steps for your emotional investigations. Good luck! 
Tiny sugars in the brain disrupt emotional circuits, fueling depression
