Webster's dictionary defines trauma as an injury or a behavioral state caused by that of severe mental or emotional stress or physical injury or an emotional upset.
This definition can be also reflected in the mental health definition of trauma: the experience or exposure to an immensely stressful, scary and or life threatening experience, and continued feeling of experiencing this (or these) experience(s) by memories of that event via intrusive thoughts/reminders/triggers. Or more simply, (from EMDR founder Francine Shapiro) "the past feels like the present"
What most often gets excluded from this definition, (including report of its occurrence), is Emotional trauma. It is often overlooked due to not having the general social acceptance or recognition of other traumas (like combat/car accidents), as it can be more subjective to the individual (such as shaming, teasing, emotional neglect or feelings of family favoritism).
Trauma can be classified in two categories. "Big T" trauma (war/combat, abuse, sexual assault, car/plane accident or crash, natural disaster, terrorist attack) and "Little T" trauma (teasing, conflicts, confrontations, being shamed).
A Big T trauma can further be distinguished as a significant event that has the individual feeling powerless and without control of their surroundings or environment, feeling life threatening.
Whereas Little T trauma are subjective experience(s) based in individual perception of the event(s), that disrupt our emotional functioning. Such as ego-threatening, shaming interactions or events having us feeling helpless as how to react. There may also be an accumulated effect of these events or interactions, such as multiple Little T events. An important note to make is the individual perception of the little T trauma: what one individual may find stressful or upsetting another may not. It is more important to focus on how the event impacts the person versus that of the event itself.
Only you can define what is traumatic or disturbing to your story and together we can focus on processing that event or those events.