baby girl won't sleep

Charmaine
Over the last two days my baby girl hasn't been sleeping at night from around 2 am to 6 am she is extremely fussy and just plain mad! This is happen a few days ago so not sure what it could be I don't wanna go to the doctor to look like a crazed first time mommy.I am attempting the baby is wise sleep schedule but there are so many! Help please !