Suddenly not hungry and more sleepy

Ok so I am just going to put this out there and see what you ladies say. My little girl is 3months and is sleeping a TON. She can sleep all night (but I wake her every three hours to eat), eats reluctantly and only on one side at night. She naps for one hour twice a day. Her eating has become a lot worse in the past few days and her sleeping much deeper and longer. Her diapers are much less wet than they use to be. I'm getting worried. Should I call the dr? Could this just be a phase? She also refuses bottles...