Identify flower from Wildflower mix

Hi,

I planted this wildflower mix in late October, and the flower attached has appeared. It doesn't look like a wildflower and may not even be from this mix. However, it's really pretty! Does anyone know what it is?

 

Looks like a Vinca

 

I agree it's Vinca (Perriwinkle) but I don't know which type. It isn't a wild flower, it must have been in the ground before you sowed the seeds.