My DS (18 months) is a fantastic eater and will usually eat anything we offer him.
He is also going through a phase now where he won't eat. You cannot force them, and if he does not eat his lunch / dinner we just take it away until his next meal or milk etc.
I definitely think it has to do with teeth, as when DS was cutting his 1 year molars he was exactly like this, and I can feel lumps in the back of his mouth where his 2 year ones are due to come through, he is also cutting the last of his Eye teeth which seems to be taking ages.
I would not worry too much about it, you could alway offer her something a few hours later to see if this would help. Have you tried freezing any fruit and trying that, it could be that perhaps her mouth is really sore, and the frozen fruit might help ease her gums.
You would be amazed at how little food can keep them going. My DS once slept through the night only eating a banana, and then made up for it a few days later.
I know it is hard not to worry, but she will eat when she is hungry. Just keep on offering her something every few hours.
Hugs, please keep us posted on how you get on.