She sounds like she might be unwell, actually. Not seriously unwell, but feeling under the weather enough that she doesn't want to eat much. It doesn't really matter at this age if she isn't taking much in the way of solids, milk should still be her main source of nutrition. I'd just let her eat a bit of what she fancies and then don't stress about the rest, keep offering plenty of milk and fluids and keep an eye on wet nappies. Yes if she isn't 100% she might lose a bit of weight, that happened with my DD every time we had a phase of this, but it's not going to hurt her unless the weight loss is severe or prolonged. Keeping her hydrated is the priority. Any concerns maybe a trip to your doctor might set your mind at ease?