My daughter stopped cooing; she is 2 months old. 3-4 days ago, she was…

My daughter stopped cooing; she is 2 months old. 3-4 days ago, she was cooing constantly, but now she just smiles and that's all. Maybe her tummy is bothering her? She is turning her head from side to side. She looks around and gets distracted when I talk, although before this, she used to look at me for a long time and respond to me.