i am a 19 year old girl. i suffer from menstrual disorder since menarche. i have been underweight since childhood, my weight is 42 kgs and my height is 164cms. i also have sinus. my concerns are my menstrual problem, weight problem, and sinus. my nose runs whenever i cry, which is very embarrassing. and my nose gets blocked too. i get a cold every month. i even suffer from constipation very often. my complexion turns brown usually although i am fair. please suggest yoga exercises for all these problems.