Welcome to health care magic.
Try to relax.
Your age is 17yrs and you have 2 missed period. Also 3 pregnancy
tests are negative.
I think you are suffering from OLIGOMENORRHOEA.
It has several causes.
1) PCOD with Over wt
4) Eating disorder
with under wt
So need to investigate properly.
Do the following test USG, LH/FSH, Thyroid study, Blood prolactin
& HCG with consultation of gynecologist.
Do regular exercise,take healthy diet.
All the best.
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