I tend to take some social rules pretty literally. The consequence can be both overgeneralizing and undergeneralizing. For example, at my current place (particular ward in psych institution) there's the rule that patients should formally not stay longer than one year. From this place, people often go to group homes, supported living, etc., for which waiting lists ar elong, so I get worried that I'm not on any waiting list yet after 4 1/2 months on this ward. The reality is that this rule is in the leaflet so that people won't come here if they have no desire to move on to a more community-based setting or fi they are not expected to make progress that will enable them to move to a community setting, and that it is a guideline to have people here about one year. However, I take the rule and obsess over it.
Undergeneralizing happens iwht most situations of social behavior expectations, when overgeneralizing won't work. For example, you are supposed not to snap at people, but that is so general that I don't understand it or can't apply it in everyday situations. So I get like "I can't say ___ to person X", etc.
Oh, as a side note, I am not literal-minded in other aspects at all, like language.