Not sure.  I thought mine were sick when in fact they were pregnant.  Very swollen bellies.  My Rosy Barbs weren't eating much (which I again attributed to sickness).  That might be one way to tell.  Are they still acting normal and swimming all over the tank?  Mine hid behind plants in a fairly dense area, I'm guessing because they knew it would be safe there for their babies. 
Again.  All this was happening when I thought they were sick, so that might not be normal behaviour.