I can totally relate to this. I have been meaning to come on and post about my aggressive toddler too.
My son is 20 months and I just find that pretty much anytime we are interacting with other kids, he always seems to get himself in a physical situation, either biting, hitting, grabbing, or shoving. He is really undistractable too, I always have to remove him from the situation. Today he threw a rock a this little girls head that was standing less then a foot from him. She wasn't hurt and didn't even cry but he could have easily hit her in the eye or something. I am so understanding the frustration too. It makes me feel like I am doing something wrong, here. Like what can I do to help him not be so physical. And why is he that way...he doesn't have any brothers or sisters to learn the behavior from...I just don't get it. I seriously don't see many other kids acting out like him.
I even was thinking about starting time-outs because distraction doesn't work but I want to discipline him in age appropriate ways, yk. Just writing this makes me frustrated. I really don't know what to do about this. I talked to the doctor and he just said that it was normal and that I should tell him a firm "no" when he does something aggressive and when he's older, I can give time-outs.
"Breastfeeding is a robust, biologically stable activity so central to our evolutionary identity that it names the class of animals to which we belong" (Breastfeeding Atlas, Third Edition)