Some situations were clear to me that I was being treated a particular way because of my race. But then others were not so clear cut.
For example, one time I was talking in Japanese with a group and someone kept repeating what I said like "He said...". I was getting angry at that as I took it to mean that they were basically "translating" my Japanese for others. But then later, I was watching a Japanese TV drama and the same thing happened on there (with only Japanese speaking). That made me think that maybe this was just a cultural thing that people do and didn't have any reflection on me personally.
Having mentored a female engineer, I've seen that if you are constantly on the lookout for signs of discrimination against you, you will find so much of it. You'll go crazy thinking the whole world is out to get you because of your sex, race, etc. It's tough because there are no doubt situations where that does happen. But there are also situations where a white man would have been given the same feedback or treated in the same way. As a minority though, you only have your own experience to go on. It becomes tough to recognize what is legitimate discrimination vs what is just ordinarily communication.
Instead my head is somewhere else entirely, and I might have been annoyed at myself for forgetting to pick something up at the store or whatever.
We've gotten better at handling it, I try to remind myself to immediately tell her it wasn't her, and she asking me what it was if I forget. But there has been a lot of unnecessary bad times that originated from such episodes...
One of the best pieces of career advice I have ever taken was from this TED talk: https://youtu.be/KzSAFJBLyn4
The section on Abraham Lincoln. Perceive no slights. It changed the way I approach people at work.
For those perceived as belonging to a privileged class, people feel free to (and in some cases relish in and are socially rewarded for) voicing their sexist opinions. A man has a lot less reason to dwell on whether a particular interaction was sexist against them, because when it does happen it is often overt.
This is not uncommon for men or woman to do, and more commonly expressed as ‘you are looking for things to point out’.
You can run your own little test. Convert the sigh to something similar like shrugging. Consider it debugging with console.logs until you find out the source of the bug.