Hi my 13 year daughter has collapsed 7 times in the past 3 months losing consciousness 2 of these times. Since the initial collapse she has complained of leg pain and weakness to the point she has had to use crutches at times as she s unable to bend knees when weightbearing/ headaches/ nausea upon waking in mornings/ fatigue and poor concentration. She received a Tdap vaccine 6 weeks prior to all of this starting so I don t kno if there is any connection.. her bloods have all come back normal and chest xray and abdominal ultrasound all normal too..