I am not a dr or health professional, but I wonder why your dr laughed when you talked about drinking during pregnancy? In general, I think many health care professionals have little knowledge of alcoholism.
FAS is incurable, but there are treatments for some symptoms. The earlier the diagnosis, the more progress can be made. Depending on the symptoms a child with FAS exhibits, you might need many doctor or specialist visits. My limited knowledge of FAS tells me that the earlier you begin to help the baby, the better the off she will be.