Some mutants didn't come into their abilities until they were entering puberty while others -like Peter and Wanda- were born with their abilities ready and able to go at will. He'd been a pain in the ass for his mom to deal with from the time he'd learned to walk. Peter tried to think of a time when he hadn't been able to move how he wanted, where he wanted, as fast as he wanted. It was too long ago for him to remember.
Shaking his head, he whistled, "I think I'd kill a guy if he called me a bitch. I'd definitely hit him and when I hit someone? They feel it. Mass times velocity aimed in the direction I want equals a pretty nasty momentum and only one guy has ever been able to remain standing after meeting it."
It wasn't the same with Jean because Peter hadn't managed to get to her to hit her. She'd just stopped him from reaching her before he could throw a punch. That wasn't the same as Apocalypse taking his hits as if he were an annoyance instead of a threat.
"Why would you call yourself a bitch? Isn't that a bad thing? I'm annoying. To normal people. Or even some mutants. I think the only time I was probably not annoying was when I was a baby or barely older than a baby. My mom never really talks about me at that age. My twin sister was too much of a problem child for her to notice anything I did. I think 'annoying' is just admitting a truth. It seems different when it's a word that's mean."