I'm so sorry this is happening to you. It won't be any comfort to you & it makes me feel ashamed of myself to admit it, but I had a nearly identical situation with my son when he was 13, except I did pop him in the mouth. I had never spanked him in his whole life, not one single swat. I don't believe in taking a hand to a person who's only 20 percent your size. It's abusive. And my mom... oh my god, how I was beaten every day for nothing & she never even tried to use regular discipline with us. She had 8 kids & my dad traveled. She was miserable because she rightly suspected my father was having affairs in every town he landed in. After he died, I found a marriage certificate on that geneaological site, in his name, in a town not too far away. I told a sister. She said she was just waiting for a bunch of other people our age to show up & tell us we were their half sisters. The marriage certificate was not him, although the name was right & spelled in the Dutch way, & he was born in Utrecht, Holland, just like my dad. Nevertheless, I'm sure my mom went through a lot. But I was so hurt, so many times, in so many ways that I vowed never to touch any child I might have, except to show him love. I was batting .1000 until the day I smacked him in the mouth.
Ironically, the first thing I did was call CPS on myself. I asked them to take him away because I didn't know if it was safe for him to be around me. They had no beds, even for the foster kids they already had. So I ended up taking him to my mother's house. MY MOTHER'S HOUSE. The house of horrors I grew up in. You know what I mean, Mama. You went through the same stuff, and more.
Anyway, I sent him to his stepfather's house (his dad was dead) & he was taken care of there. But in a very short while, he did something bad to himself at school & the teacher flipped out & he was taken by ambulance to the big trauma center in Seattle, then shipped off to the mental health facility at University of Washington. I was doing everything I could to reunite, but they wanted to keep him. He ended up in the foster care system & immediately ran away. He was a missing person for six months.
It's painful to talk about, although we've discussed it together & I've apologized & he's never disappeared again. This year he'll be 40 & he's the most decent, loving, caring & charismatic man I've ever met. He is beloved in our town. He never pays for a meal or a cup of coffee locally. When he walks in the door of a restaurant or coffee shop, he's like a rock star. Everyone gather around him, hugging, loving, offering things. It's really amazing.
I get complimented for doing such a good job raising him. I did do a good job, most of the time, but there were some painful detours. I always tell people, "He just popped out like that, I had nothing to do with it."
Just keep letting him know you love him but his behavior is unacceptable. That's the best thing a mama can do. Who knows how he'll turn out? I suspect he'll be fine, just going through this uncivil phase where he's targeted you. You're stronger than he is. He'll figure that out eventually.
Free advice may be worth what you paid for it, but I just wanted you to know you are not alone. I could have lived without my kid's little stumble in his life, but it happened & we healed & came back together.
I know something that always helps but it's hard for people to do: take deep breaths, in, then out, over & over with your eyes closed. It may not seem like much, but your body can't resist it. It's calming.