Agressive toddler

Im coming to this app in search of guidance and advice. Negative comments wont be acknowledged.

My son is will be 19 months next week and for the past 6 months has been a MONSTER

now this is my first child and i am a single mom. So yes i am overwhelmed and exhausted. My son does not listen. Period. At all. I know that comes with the age but i will tell him repeatedly to stop and he wont. Ive tried redirecting him (if I take something fron him he shouldnt have i replace it with something he can play with) he hits amd screams ans kicks and now that he has 12+ teeth hes biting! But he thinks its funny. He just laughs. We started trying harder discipline by smacking his hand and rather than saying NO (because he now repeats that and will scream it back to you) saying "please dont hit". Or "thats not nice you need to be nice". "Mommy loves you. Show momma how you love nice." And it was starting to work.. But now if you tap his hand he will smack himself in the face. The past month has been the worst. When he gets mad he smashes his head on the wall or floor, smacks himself so hard he leaves marks and is now beating on the dog. We still try to redirect him and use positive language such as "please dont hit our friends" and we always show him how to pet the dog nice (although he does know better) so i guess im just asking is that normal toddler behavior and if so what else can I do to help him? Ive made it a point to not engage with him while hes having a tantrum but sometimes it makes it worse.. And thid is no longer a few incidents a day. He is constantly like this and terrorizes my house. He comes by and swipes everything off the table, tries to climb everything, tears everything apart and just laughs at you. Ive tried keeping him busy throughout the day to keep him distracted but he would rather destroy my house than read books, play with toys or watch movies... Any positive advice would be appreciated.