I would visit a doctor as soon as possible. It could also be because of your underweight but the doctor will most likely sort it out for you and help you.Hope this helps!
Hi Krissy,thanks for ur reply, iam overweight, for my age it should be around below 60.But this is the first time that iam facing this problem, since i matured from 13 years to 24 years in this span of time i never missed my period even once, but all of a sudden, this change and still it contuniung till today, iam fed up of using pads for 2 months,