Need some help

I have a four year old son, he stays with me mon-fri then goes to dad's Fri night threw mon morning... idk if this is part of it but... he screams and cries at every little thing. I say getting your shoes on he cries, pick up a toy he screams and cries, he has so many emotional outbursts threw out the day. I don't know what to do it him, I can barely talk to him because he just screams or cries....I don't know what's wrong with him... I'm so lost....everyone gets frustrated with him fast because of his outbursts.