Unhappy customer

I have bought the boots from online, but the shoes are very uncomfortable so much that i cannot walk with them because the cut is too small, I'm usually a size 4 but i sized up but the shoes are still painful, and it makes my ankle so painful. I asked to return the shoes even though i wore them once and get a bigger size? Because i really love the shoes but i cant wear them as they are too uncomfortable and make my feet.

I was that they won't be able to accept the boots back since they have been worn.

Very disappointed