From Google/urbanoptique.ca,
>Several factors, including environmental irritants, sweat, dry eyes, blepharitis, and allergies, can cause the burning sensation from your tears.
Edit: to put in my own words, there can different reasons why your eyes might burn or sting when you cry, a lot of them having to do with external circumstances, and sometimes it can be because of hormones, as I also learned while looking for an answer.
This obviously doesn’t go into depth, but it could be a jumping off point!
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