I don't know where else I could've asked this and feel a bit silly doing so. But, I am writing a sci-fi story and the human character is punched just under the ribs by a very strong alien. I want to know what kind of non-fatal, yet serious enough to need medical attention injuries I could give the character to make the scene feel more "real"?. Thank you for your time and sorry for asking such a question I am unsure of places I could get such information from.