Military mamas

I went out of town and smoked pot while there. Then found out I was pg. I need to confirm on base to be referred to a reg birthing center. Our base has a bad history of delivering babies...as in...seems as if they just don't know how. Are they going to drug test me? I don't typically smoke (used to every day before my husband joined the military but hadn't in 8 months). They aren't going to care if I did it when out of town, just the fact it happened. What do I do?? I don't want to get my husband in trouble and need to be referred somewhere else. Should I wait until it's out of my system to make an appt? I'd like to get an early scan to make sure placement and development is on track but am not sure what to do. LMP is saying I'm 6+4 but I think I'm really closer to 5+6. Suggestions?