Hello girls, has it ever happened that because of your baby someone el…

Hello girls, has it ever happened that because of your baby someone else's child got hurt? My son is 2.1 years old and bumped into a 2.5 year old boy. The boy fell hard, I felt my heart jump in my chest. How can I calm down? And how can I explain that you shouldn't push and hit each other? I keep telling him but he doesn't seem to hear or understand me.