Question

I rarely get upset when i'm working meaning?

Answer 1

You rarely get upset when you're working because you are most likely focused on whatever you are working on, keeping you too occupied to worry about other things.

Answer 2

This sentence can have two different interpretations. The first one can be a literal meaning from the words which construct the statement. And the second interpretation can have a figurative meaning, that is, what we can imply beyond the words present in the sentence.

First the literal meaning:

"I rarely get upset when I'm working" means:

That it is a rare or seldom occurrence that I can feel a feeling of discomfort or discontent

Second the figurative meaning:

I enjoy my work too much that I am very frequently in a happy state of mind that I almost never feel angry or displeased while I am working.