Nub theory??

Can anyone tell me if I have found the nub my scan picture it's at 12 weeks 2 days if I have can you tell me if I'm expecting girl! Me my husband and Nan think it means girl my sister thinks It means boy! I thought pointing down or middle at less than 30 degrees is girl! Up and at more than 30 degrees is boy! I've zoomed in on bottom picture so you can get proper look