My Baby Girl Is 2 And Half Month Old. She

My baby girl is 2 and half month old. She is very good with feeding winding sleeping everything, up until now. She has had a routine but since last 2-3 days she has been crying violently . During the day and night. She only stays calm when she's asleep or when she is feeding. As soon as she opens her eyes from sleep or stops drinking milk she cries very loudly and wont stop