Hi, i'm 30 years 6 months old, i have missed my period for the 3rd month, i have done pregnancy tests and all negative. i have a baby who is 10 months and from the time he was born my periods were regular, never late. no spotting only headaches ?

It happens sometimes: In a woman with regular periods, some causes of a late period include: excessive weight loss or weight gain, increased exercising, emotional stress, having an illness, traveling, medicines (like birth control pills), hormonal imbalances (such as brain, thyroid, ovary hormones), etc… Seeing a doctor is a good idea if symptoms are persistent, recurring (as in this case), or worrisome.