Potential miscarriage

I’m looking for some advice my girlfriend and I (im male btw) we have just been for an early scan yesterday (02/04/19) we had no reason to go for an early scan but because we didn’t know the exact date of her last period only that it was sometime in January they got us in because the midwife thought we might have been further along because when my girlfriend took a pregnancy test on 22nd of feb the clear blue test said 1-2 weeks but the midwife said it could be further along that that. Anyway they struggled to find anything at first but finally did and we were told we had twins but they weren’t very hopeful and they believe she may have miscarried. They have however referred us for a weeks time just in case it is too early. We are both panicking and expecting the worst, just wondering if anyone else has experienced this and not really been told much about why she might have miscarried.