Help! I Need Advice Re: Shoes (should I Keep

I am the mother of an October/04 bride. I purchased a long two piece dress & jacket in navy blue. It is very plain but elegant. I has a thin line of navy beadwork down the front. I bought a pair of slip on shoes made of clear plastic that has 2 thin satin gold straps through the top and a sparkly decoration on the side. The heal is also clear. They are very pretty but are they ok to wear in October with a very plain dress? Also, you can see a bit of my heal (foot) . Is the dress too short?
I can still return the shoes but am finding this a real dilemma! Thanks so much.