Creepy guy who follows me

I went to my local Walmart. As I was walking down the cereal aisle I notice a creepy guy following me around the aisle. He kept making eye contact with me, and I was scared so I decided to walk towards the other side of the aisle. But then he would walk to the other side too. He would walk around the aisle making it so we were right next to each other. I went to the checkout counter, but then he followed me there too. Then he asked me if I needed a ride. I said no, and he walked away. But I still felt really scared.