Loss of appetite after 5 day vacation.

Hi everyone, Today only I am back from a 5 day vacation with my 1 year old daughter. During the trip she was mostly on formula milk but we kept on serving snacks, fruits, grilled fish and paneer but she didn't really had it much. Today even after returning she is not showing any interest in food. Whatever we try to feed she will have a bite or so and then will reject it. It seems she has lost her interest in food and doesn't want to eat. Before going on vacation she was having 3 meals and 2 snacks on her high chair and 400 ml milk in a day but now it seems very difficult to feed her anything. She ís mostly sleeping and is only taking milk around 600-700 ml. Why is this happening? Is this a phase or is she tired? How shall I get her to regain her appetite? Please help. Regards