Physical expressions of emotion can be problematic, even though they’re justified by the “Show, don’t tell” mandate. But there are often better, more artful ways to give us insights into the interiority of your POV characters.
Is it better to format character thoughts with quote marks or italics? I say neither. No special formatting is necessary to signify character thinking. You just need some solid narration.
Should you use synonyms for “said”? Some writing advice claims “said is dead”; others look disparagingly upon “saidisms,” the fancier cousins of “said.” Here’s the rule of thumb.