Tantrum

My son is going to turn two in November. He has just gotten really bad. I honestly, don't know what to do anymore. Every time we go to the mall or someones house he throws himself on the floor. He acts really bad. I don't know if it's because I started working when he was 2 months old and my mother-in-law takes care of him, but her kids are like that too. Of course, they are older and understand more but I dont know if it's because he sees all of this at her house and he thinks that it's okay for him to do this things or what.

He has been going to sleep real late too and he just wants to be watching movies. He hardly wants to eat. I want to know what to do. I need advice because it is very frustrating for me and my husband.