What Causes Passing Of Dark Stools Plus Mucus Discharge In Children?

My 1year old normally does 1-2poos in the morning only . She had her 1 year shot and also go a virus and a tooth in the same week (2weeks ago) the last 2 days she wants to eat all day I'm trying to cut a breastfeed out so yesterday gave her a slippy cup if full cream milk diluted with water, she just had a bit. She had dairy before. Last night she did a poo during the night and keep waking every 2-3 hours the poo smelt like off milk and was dark with slime in it ? She does have a lot of fruit too so there was blueberry in it too??Could this be the milk or just the virus ( which she finish but still has a little rash on her face) teething ??should I still give her a2 full cream milk in a cup today after lunch ??Thank you,Tania