Brief Answer:
Needs work up and management

Detailed Answer:
Thank you for asking

I read your question and i understand your concern. Three periods missed with negative pregnancy tests and associated symptoms of fatigue, constant sore throat, through out abdomen pain needs evaluation for other causes of amenorrhea. Hormonal imbalances are one of the common cause. Needs work up for thyroids, cortisol hormones, polycystic ovarian syndrome . If overweight losing it will help. You should visit a local hospital and find a gynecologist . They will assess you for causes of menstrual irregularities and then decide the management plan which will mostly be diet lifestyle modifications and use of oral contraceptive pills along with some other cause based treatment.

I hope it helps. Take good care of yourself and dont forget to close the discussion please.

Regards
Khan

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