My daughter is congested...?

my daughter is 28 days old and has been congested for three days now i used the saline spray and suck out mucus but it comes right back she has a appt with her pedia on 8/31 but i am really worried it may be affecting her breathing through the night when were sleeping but she does take her binky all through the night and it doent seem to affect her at all even when she eats her formula :) but i feel so bad cause i cant blow her nose for her am i worrying for nothing or not? FYI: she was a csection baby and had fluid in her lungs and had "grunting:? could this be an effect of that running its course? how long should it last before a trip to e r is made?