Could my bird possibly be sick? please answer!!!?

Shes a female zebra finch. She looks a little sad form her eyes. She looks a little puffy and she like 1 year old. i think a little bit less. probably like 9 months i think. well she does have a son and hes about 5 months old. she still does lay eggs but doesnt warm them. she still moves her head a lot and jumps too. i dont have money to take her to the vet and my mom will just tell me she looks fine. she wont wanna take me cuz it costs 70 dollars.could she just be getting read to lay more eggs? please help me!! if she is sick i will cry all my tears out!!!!! last time my male finch looked sick to me but i covered the cage with a towel, gave him fresh clean water and put a lamp near him, and i kept praying he will be fine and he was. should i put a lamp and towel on her cage?