Can not getting enough sleep give you diseases? such as cancer?

Lack of sleep wont cause cancer but can give a lot of problems systemically. A few example of these side effects are: digestive problems, blood pressure problems, increase cholesterol level, and since you're only 14, it can also affect your immunity. It is normal for an adolescent to have an abnormal sleeping habit. This is due to the secretion of their hormones. However, if you don't want to develop complications early in life, better start correcting your sleeping habits. Partying all night long is OK every once in a while but you have to go back to normal sleeping patterns after that. You won't probably get the different diseases in 3-4 weeks time per se, but your body will start showing signs of fatigue and some of the internal organs will start showing abnormality in their functions.