Can you develop insomnia on your own if you change your sleeping habits and stay up all the time?

Of course! I know people that are very successful making themselves do silly things like that!
Sleep Hygiene. Our body likes routine, stability. If you change that by staying up, you will experience sleep disturbances. To get back on track, create a bed time routine -- warm showers, room should be on a slightly cooler side; no tv, no computer. Learn relaxation exercises to help put your body in a "i'm sleepy mode" :). Don't use your bedroom as your office.