Drank alcohol before knew you were pregnant

Marcie • 29. 1st baby
Did anyone drink before you knew you were pregnant? . I drank for 7 weeks prior to finding out. I'm really scared and terrified after finding out facts and Googling fetal alcohol syndrome. I would never hurt my baby on purpose. The doctor said the baby looks great on ultrasound at 21 weeks but they can never detect fetal alcohol syndrome until the baby is born. Anyone Help? Comments? I'm driving myself crazy with guilt