This is my 1st time fasting w/ my church.my period is 5 days late and haven't been intimate in 6 months. is fasting causing period to be late?

Hard to guess...: 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, etc… Seeing a doctor is a good idea if symptoms are persistent, recurring, or worrisome. It's possible that fasting several days can cause a late period.