I would call your healthcare professional (HV or probably still your midwife at this stage) as sometimes jaundice can cause bodily fluids to be yellow. My daughter had yellow everything until she was about 4 weeks old! Snot, poo (which was normal as breastfed), skin, nails, eyes... everything! She had jaundice and the pigment in her skin didn't completely go until she was about 3 months old.