I think I might be fictionkin of a character, and I feel drawn to the story this character comes from, but at the same time it makes me feel stressed out for no apparent reason. Is this a common fictionkin thing / how common is this for fictionkin?

Its pretty common to feel anxious/stressed about the story you come from, especially if that life had a lot of negative things happen to you. And even if the portrayal is a more positive one, its definitely common to still feel weird/cringey/embarrassed about seeing you on screen/on the page.