Flat Nipples, Breastfeeding Help!!!

Has anyone with flat nipples had any luck breastfeeding??  My 3 day old baby won't open wide enough to latch is problem 1. She's eager and wants to feed but gets frustrated.  Problem two (my biggest concern) my nipples are on the flat side. We've been trying nipple shields- still not latching correctly but we are continuing to try before every bottle. (We are supplementing until my milk comes in.) worse case scenario is pump and feed but was really wanting to breastfeed her!