My kid went from being a sweet little boy to a whiny screaming crying at everything tantrums kinda…

My kid went from being a sweet little boy to a whiny screaming crying at everything tantrums kinda kid ever since the baby came home. Why !? 😩😭😤i hope its just a stage and he will get better soon bc honestly every time i change his diaper he screams bloody murder and kicks me or when he climbs on table and we take him down tell him no he screams top of his lungs. Anyone else has this problem and how you deal with it? He used to be cuddly and now every time I pick him up he pushes me away kicks and screams 😳🙄i feel not wanted and a bad mom for always telling him no to things and not giving him enough attention bc of newborn baby