VERY normal! My son did the same. All I did in the end is to tag my mom along to keep an eye on him while he explores. He is now almost 2 years old and decided that to sit in the trolly with mommy or to walk with mommy is much safer. But they do tend to get irretaded if you take to long, due to the stupid ques you have to stand in or due to those people standing in the middle of the floor chatting away while you have to say a thousand times, ' exuse me, exuse me, F%$K*%G exuse ME! Sorry, just had to get it of my chest

But then I ask my mom to take him to go and ride those car thingies they have at most shops/malls.
Just try to get someone to go with to help keep an eye on her. It eases the tension on you.