Bad customer service

I bought a shoe at steve madden Mall of Africa and worn it once maybe for 3 hours and it was uncomfortable then I went back to them then told the that the shoe is uncomfortable and I worn it once and they told me that They won't be able to exchange it for me cause I've already worn it,so what am I supposed to so with an uncomfortable shoe,Yes it is my size and I fitted it before buying it and it was okay and mind you fitting is only 2-3 minutes. I bought the shoe on Thursday the 23rd of November and worn the shoe on Saturday the 25th of November and that is the very same date I tried to exchange it for a different size.