I'm starting to get worried! Baby girl five months old isn't eating normal she used to go 4 hours…

I'm starting to get worried! Baby girl five months old isn't eating normal she used to go 4 hours between a bottle and I try to feed her and she refuses it. I have to force her to take it. I'd call her doctor but they never understand so I'm asking you all. What do you think? She shows no signs of teething.