GR- Praise and Criticism In The Main Characters

The main character in the book JERK, California is Sam Carrier. In the book, I’m trying to figure out why the author changed the main characters name to Jack Keegan. I think Sam was praised and criticized by the other characters in the book, for example, his mom Lydia, his stepdad Old Bill, his real dad’s friend George the Coot, and his crush Naomi.
It seemed like Sam’s mom cared about him in the beginning of the book, because she was worried about him having tourette’s, but now after marrying Old Bill it seems like she doesn’t care much of him because she takes his side on everything. She praised him then would criticize him for not doing what Old Bill said to do.
His stepdad Old Bill shows no praise to Sam at all in the book so far because he teases him and treats him like he’s no good. He blames the tourette’s on everything and it’s not Sam’s fault that he has this syndrome. He will show criticism towards Sam because he is not his real son. Old Bill shows he loves his biological son Lane, because there is nothing wrong with him. I feel it’s not right for him to degrade Sam down like he does because it makes him feel even more down on himself. I feel that Old Bill won’t change in the book because he will keep criticizing Sam for his own being. I also feel that the tourettes is getting worse because of his stepdad.
His real dad’s friend George the Coot has showed praise and criticism to Sam because he offered Sam to live with him, has Sam help him with the gardening, wants him to know more about his real dad. He showed a lot of criticism towards Sam by him doing cruel things with him behind the truck, is making him change is name to Jack, because his father wanted it to be that. In the 2nd part of the book is when it’s going to talk more about “Jack”. I feel that he shouldn’t have been pressured to change his name because nobody needs to change their name if they don’t want to. It must be something to do with the headstone that Coot showed him on the bulldozer blade because that’s where it all started.
His crush Naomi has showed praise and criticism to Sam by her keep popping into his life when he is doing things for others. Sam thinks that she likes him because she keeps coming back. Well it seems like she does and doesn’t because her friends think he’s a freak, and she thinks he is and sometimes isn’t. There were instances in the book that she thought he would be a freak and then some she seemed like she was starting to like him more as person. She shows criticism by being two-faced to him because as she steps into his life each time he sees her, his heart sinks, and she doesn’t realize that he is deeply in love with her. I need to keep reading and see what happens if she ends up popping up into his life more or if she’ll ignore him completely.
I’m hoping that Sam doesn’t give up on loving Naomi because it seems like that’s all he needs in his life. As I keep reading, hopefully things start to happen more and keep getting more interesting, because it seemed like I was getting lost in the beginning, but as I keep reading I noticed its getting a little easier to get the idea of the situations.