I'll answer yours now..
Yes I am a British Citizen.
I do a lot of intense training at the gym, I make sure I run 5km and do the sets I do. I can't remember once when my asthma has effected me physically! I just wish they'd test you on how you are at the age your applying; rather than looking back when you were 10!
About the engineering thing. I know it involves maths, but that maths I can handle, same with astronomy, just not astro physics!