In an interview with WWE.com, WWE Doctor Chris Amann said the following about the current eye injury sustained by John Cena:
“John Cena had been [competing during] last weekend’s Live Events when he sustained a corneal abrasion during his Live Event matches. This evening during the attack by Rusev, John Cena’s injuries were exacerbated. As mentioned [on commentary], those injuries were a scratched cornea and a ruptured blood vessel. “We’re going to do periodic eye exams to make sure the scratch on his cornea is healing and he will be ready for WWE Fastlane.”
Cena’s eye injury is indeed legit, but it has been worked into the current storyline with Rusev heading into their match at the Fast Lane PPV on February 22.