Hi Chen
Good move re getting instruction. Most of us (especially on here) spend a lot of time and resources on learning how to deal with external threats (whether they happen to us or not) little realizing that over the course of our lifetime we are our own worst enemy. For the vast majority of people YOU are going to be the person that does yourself most harm! No one else! So its worth making the time to take care of yourself.
This is a core idea in many traditional Chinese systems:
i) Build health
ii) Develop fitness
iii) Learn how to fight
Its a pretty good order of things IMO. No point in doing 3 if you aren't taking care of 1 & 2 first.
You are a bit off with Qi Gong though. Like the term Kung Fu, Qi Gong has covers a vast range of (mostly healing) practices. Most are designed to improve health and vitality, some are even used to develop martial ability (some Qi Gong sets, like Shaolin Ba Duan Jin are a pre-cursor to Iron Body training).
Qi Gong can involve accupressure, but most commonly it is a set of movement/breathing/postural exercises to develop the body. If you imagine a cross between yoga and Tai Chi (though that isn't what Qi gong is!) you will get an idea of what it looks like.
Better yet, here are some popular Qi Gong sets:
Ba Duan Jin (this isn't the Shaolin version though!):
http://www.youtube.com/watch?v=71MN9sX-tWsWudang 5 Animals:
http://www.youtube.com/watch?v=n5FMhYvxvPYMost Qi Gong looks like the above. As I said, it is easier to learn that Tai Chi for most people.
I practiced Ba Duan Jin, which is primarily designed to help with the lungs and kidneys. I feel a lot better from doing it, and my inhalation/exhalation capacity has greatly increased (even though I was doing a lot of running, Qi Gong has brought it on another level!).
Many Taiji/CMA teachers usually know some sort of Qi Gong (see my point re the order of study in CMA). So you should be able to find someone to show you. If not, let me know, I'm sure I can track down someone!