Every morning, an Illinois teen wakes up and thinks it’s June 11—the day she suffered a traumatic head injury. Riley Horner’s memory resets every two hours.

The teen said she had a calendar on her door and when she looked and “it’s September and I’m like, ‘Woah.'”

Riley was accidentally kicked in the head months ago by a crowd-surfing student at a dance. She subsequently had dozens of seizures and countless hospital visits, but her symptoms remained a medical mystery.

The first doctor believed it as a concussion and simply sent her home on crutches.

“They tell us there’s nothing medically wrong,” said her mother Sarah Horner.

Sarah said the doctors can’t see anything. Even MRI and CT scan, they can’t see a concussion. There’s no brain bleed or tumor.

Even Riley’s memory wiped out the simpler things in life. The teen girl carries every textbook, notebook, and pencil with her throughout the day because she can’t even remember which locker is hers.

In order to keep track of her day during school, Riley needs to leave herself detailed notes. She also takes photos of them on her phone, and set an alarm for every two hours so she can brush up on what she has forgotten.

Her mother said, “My brother passed away last week and she probably has no idea.”

She added, “We tell her every day but she has no idea about it.”

“I know it’s hard for them as much as it’s hard for me. And people just don’t understand. It’s like a movie,” Riley said.