I am all dressed up, sitting here quietly with my parents. The flowers are pretty. The music is starting. Here she comes down the aisle. I wish they would hurry so I can have some cake! Where am I?

At a wedding.

Based on the information provided, you are at a wedding ceremony.

Based on the context provided, you are most likely attending a wedding ceremony. The presence of parents, being dressed up, the mention of flowers, and the bride walking down the aisle are all common elements associated with a wedding. Additionally, your mention of wanting to have some cake suggests that you are likely at the reception following the ceremony, where cake is traditionally served.