My 20 month old is so hard 😭

My son is so difficult lately. He doesn’t listen to my husband and I at all. He purposely hurts us, (pulls out hair, pinches, slaps and bites) he does nothing but yell all day. It’s like he’s never happy anymore. I try to play with him, read books, go outside and to the park and it’s just the same every single day. My patience is really running low and I’m exhausted trying to make him happy. On top of that he never eats anything or will only eat pure junk. I’ve tried so many things and he just will not eat at all unless it’s chicken nuggets or pasta. I’m just at a loss with him. I’ve brought all of this up to his pediatrician and they just say it’s all normal and a phase they go through but I feel like my entire house is miserable because of it and I hate it. I love him so much and that’s all I want is my happy, smiling boy back. I feel like he hates me and doesn’t want to be around me at all. I just don’t know what to do.