I was sick in mid october, last week and now i'm sick again. is it normal to get sick this many times? how can i preven getting sick so often?

Depends: It depends upon what you mean by sick. Are you getting colds? During this time of year many people get colds and viruses. They best ways to protect yourself from this kind of infection is to eat healthy food, get plenty of rest and always wash hands frequently. Avoid crowded places where people are coughing and sneezing and don't smoke. Good luck to you.