oh thats hard... has she had a temperature? I find it so confusing when there isn't something very obvious to go on. I usually think if their demeanour has changed, tired & teary, lethargic or depressed than its worth getting checked out straight away. If she is still happy & running (or moving) around like normal than it could be teeth & worth keeping an eye on.

Matilda has a sensitivity to dairy but it showed up as a milk intolerance when she was started on milk. Within a few days of introducing whole cows milk into her diet she was having mustard coloured loose poos. And as soon as she went back on to her formula the poo stopped.

Goodluck!!