Wedding shoes

So I bought 2 pairs of Bella belle shoes when they were 30% off. I want to wear blush shoes but the flats no longer came in blush. So I decided I would keep the pair I like and return the other. I don't ever wear heels the blush are a kitten heel. My dilemma is the flats are big in the back slightly tight on the side(customer service suggested I use a heel liner). And the blush ones fit but aren't the most comfortable. Should I keep uncomfortable shoes that may feel better once I break them in or keep the flats and add a heel liner? Or return them both and find different ones. It just sucks because they are beautiful shoes. I wanted them to fit so bad.