Even if you had a c section, all the fluid is cleared by six days. You can try getting a little nasal sucker and auctioning her nose if you think it is that. Does she feed well and putting on weight? This is a good way to tell if she can breathe properly as babies have to breathe through their nose, so if nose is blocked they can't feed. If it is still there in a few days I would suggest getting her checked out again.