My baby is 2 months old and suddenly she has begun crying for no apparent reason and she is inconsolable. :( She rarely cries during the day...only late at night...but she just woke up from a 3 hour nap crying. I tried to breastfeed and she started crying inconsolably. I changed her diaper to see if that would helped and she cried even harder, even to the point where she was choking. She literally never cries during he day...especially this hard.

What is wrong? I'm so worried. She's NEVER like this. She's typically very happy and smiley all day long.