Reverse cycling? Or hidden pain?

I have a 4 and a half mo baby girl who only will eat at night. During the day she refuses to eat or only eats small amounts. Needless to say she is awakes numerous times at night. She's formula fed, & the started eating solid foods like avocados & oatmeal cereal every other day for about the past 3 weeks (on doctors approval). But every time I try feeding her during the day she fusses and refuses the bottle or solids. Besides that she's fine very active & healthy baby.

Anyone else had/have this problem? Please help!!