My child ate paint?!

God I feel like a terrible mother but I've searched the paint online and have found nothing helpful online. I was painting my kitchen with Ace hardware royal brand paint. I barricaded the area but my Son got through and as soon as I looked at him he did what any other toddler would. He put his hand on the wall then immediately to his mouth 😓 of course my initial reaction was to freak out, I ran him to the sink and cleaned all of the paint off and made him drink some water, do I need to take him to the ER? He seems normal but I'm very worried. Help?!