My size doesnt fit :(

I bought a pair of shoes @ Aldo's. When I went to fit the shoe, it felt so comfortable like a dream. I bought the shoes and wearing them once. My feet was so hurt could not even walk the next day. Not sure what could be the reason? I wear a size 5 and bought size 5 but would never be able to wear those shoes again after only wearing them once. Could that really be the right size?<br> <br> Please assist