What constitutes an emotional disorder?
Bullis, at al. (2019) tackled this very question this month, and outlined criteria to determine what an emotional disorder is:

The disorder is characterised by the experience of frequent and intense negative emotions;
There is an aversive reaction to the emotional experience itself that is driven by the individual's diminished sense of control and negative appraisal of the emotion; and
The individual engages in efforts to dampen, escape, or avoid the emotional experience, either preemptively or in reaction to the onset of a negative emotional state.

The paper also expands on each of the criteria and pointed out in the summary that

these criteria would only be considered an emotional disorder if the associated distress and functional impairment were chronic and significant. [emphasis mine]

The term chronic is well defined within the fields of medicine and mental health, but the question now arises as to how significant is significant in order to say that the criteria can be considered?
References
Bullis, J. R., Boettcher, H., Sauer‐Zavala, S., &amp; Barlow, D. H. (2019). What is an emotional disorder? A transdiagnostic mechanistic definition with implications for assessment, treatment, and prevention. Clinical Psychology: Science and Practice, e12278. doi: 10.1111/cpsp.12278