Joining The United States Air Force ~ Requirement Question?

I'm considering joining the Air Force when I'm older, and if I did I would like to become a pilot. Right now I'm 15 years old, about 5'2 or 5'3, and around 110 lbs. I'm pretty sure I'm done growing, and I also have asthma. I was wondering, under these conditions, if becoming a pilot is even possible? Or if I should just forget about it now...