Going to Madrid/Toledo in 3 weeks?

Hi, I'm a 17-year-old girl from the US and I'm going to Madrid/Toledo in 3 weeks for 10 days. What should I bring? I have to pack light.......I bought a sun dress and two skorts today (khaki and white) because my teacher said that they don't wear shorts. She also said that natives don't wear tennis shoes, so I might borrow my mom's sandals. The tops I have are short-sleeved cardigans and blouses with belts, and I have denim bermuda shorts. Would these be acceptable?? I'm trying to not look like a tourist. Anything else I should bring? I have an adaptor for my camera charger. What should I expect the nights to be like? Hot? I have t-shirts and shorts for bed. I also have Euros and a purse with a zipper.