One of the things people have noticed is that the fictitious Stolz der Nation (Nation's Pride) in Inglourious Basterds, which is about the career of a military sniper, bears similarities to American Sniper (also about the career of a military sniper).
Obviously there's no way Quentin Tarantino could have predicted American Sniper existing when he made Inglourious Basterds five years earlier (and to be completely fair, the fictitious film is clearly a thin propaganda piece whereas the recent real life film is an adaptation of an autobiography) but remembering this comparison and the controversies around Chris Kyle's mental state made me notice something - they don't really expand on it too much but it appears Fredrick Zoller is uncomfortable with the film and its recreation of his exploits.
Plot-wise, this serves the purpose of getting him to go pester Shosanna during the movie but I'm wondering if we're supposed to be reading more into his discomfort level, like is he experiencing PTSD or is he just embarrassed (since in the fictitious movie he played himself) or could some amount of the story he's famous for be exaggerated or inaccurate? (something that plagues the more recent modern story).