“hacerse mala sangre” [idiom] – “to get worked up [about something]”
This phrase popped up in a translation I was working on recently. It was the translation of a book about the Road to Compostela, the pilgrim route across the north of Spain, and the original quote was “en la vida no hay que hacerse mala sangre“. After trawling the online dictionaries and coming across this handy blog about the origins of Spanish sayings, I eventually settled on this wording in English: “you should not get worked up about things in life“, which I’m not 100% happy with, but I’m not going to “make a big deal out of it” (which could be another translation of the phrase).
We can also say “no te hagas mala sangre“, which means “don’t let it get to you” or “don’t get your knickers in a twist“. Note to non-native English speakers: this last phrase in English is extremely colloquial, and best only used when talking to good friends!