My daughter same as yours. This week I'm starting to starve her cause everytime I give her food, she only eat a few teaspoon. My doctor told me to dump the food in front of her if she don't want to eat. Don't give her anything until her next meal, you can give her water only. I did try this but my daughter is very stubborn and she wasn't hungry for 12hours. In the evening the doctor told me to give her 4 oz milk only so no full stomach. She did cry in the evening for the 1st night but we just let her cry. If you want to try then you must insist and I don't know if it works or not. Let's keep in touch and see what happen.
I'm worry too cause my daughter is not those fat baby and she is always at the bottom of the curve. I do hope this will work for her.