14 year old period

[Elise]

Hi my name is Elise and today I’m feeling sad and in desperate need of guidance for my 14 year old daughter.
She started her period 20 months ago and vomited when it started. We thought maybe she had a tummy bug at the same time. Since then she has been severely unwell every third period. On day 1 she is bed ridden and vomits bile/gags every hour or so. On day two she is still bed ridden but not vomiting. On the two periods in between she has cramps but isn’t bed ridden.
She is otherwise very strong and healthy.
Any advice would be very gratefully received.