LZ, don't be panic; it does not help anything. Be mature, and calm down in the first place. To your question 2, you need to actively contact school, and see if additional recommendation is acceptable and encouraged. Plus, I recommend you to do a campus visit - this is definitely not additional material, but additional effort. You wanna show that you really love the school, and would like to have a first-hand touch. There are tons of things to do while on campus - attending classes, chatting with your targetted club leaders, and probably sharing your experiences and goals with relevant professors. Good luck!