Am i addicted to cigarettes?

last 4 days i tried smoking out of my curiousity and bought a box of cigaratte ( i tried smoking 1 a day, with a total of 4 cigarattes), i gave the box of cigarattes to my friend as i have satisfied my curiousity and get sick with it ). however, now i feel like smoking more, last time i even went to my house roof to smoke, so that my parents didnt know that i was smoking.am i addicted already to cigarattes? my friends say that it takes a long time to get addicted to cigarattes, but every time i see others smoke, i feel like i wanted to? am i already addicted to cigarettes?