Hi last month i had a 3 day light spotting period and now i'm 6 days late this month. were ttc but missed last month, but not feb. what could this be?

Can check preg. test: Pregnancy is the most common cause of a missed period. If not pregnant, other causes of a late or missed period include: excessive weight loss or weight gain, increased exercising, emotional stress, having an illness, traveling, medicines (especially birth control pills), hormonal disorders, etc… a visit to one’s ob-gyn doctor is a good idea if symptoms are persistent, recurring, or worrisome.