Please tell me I’m crazy

My 9 month old discovered how to shake his head no. But now he does it very often. He will be sitting in his high chair eating and do it. He will play with his toys and do it. We’ve raised him in a noisy household (we have a dog, keep the tv on a lot in the background, etc) and yesterday he had his ears checked for something unrelated and no signs of ear infection. Am I crazy to be concerned this could be early signs of autism? He makes eye contact and is making normal baby noises like goo and mamamama. Please tell me this is typical behavior 🙏