A Kelly Clarkson concert. What to wear, what to expect?

I won two tickets to a kelly clarkson concert. The tickets are for lower balcony. Does this mean i will be sitting in a seat or do most people stand up during the concert, in the balcony sections?

I plan on wearing dark wash jeans and tennis shoes (i dont want my feet smashed as im coming and going so no dress shoes or open toes). So.. what type of shirt should i wear? do most girls just wear dress/club tops or comfy tees?