Let me know your opinions

Just wanna know what you guys think. I went out with my 2 month old baby and he's on formula. I packed some milk powder just in case he's hungry. Is it normal that i feed him in the public? Because idk why people was staring at me. Do you guys prepare your milk and feed LO in public too? My baby vomited too, think he drank too fast. Almost everyone there was like silently judging me. Should i even feel embarrassed that happen?