Kirby's final England appearance before her international retirement was in the 6-0 Nations League win over Portugal in May
Fran Kirby felt for a while that something wasn't right - the fatigue, the nausea, the persistent brain fog. But it wasn't until she collapsed in her hallway that the symptoms became impossible to ignore.
She regained consciousness thanks to a slap across the face and was told paramedics were on their way.
"I just got really, really extreme chest pain. Like something that I've never, ever experienced before," Kirby told BBC Sport.
"I didn't know what was going on. My head started to get really dizzy and I remember just saying that I've got to go and sit down.
