yeah if you stopped and felt like shit you do have a problem - you're addicted. addicted in terms that your perceive high as being normal state and want to continue being in this state
the shit feeling is withdrawal effect same as tobacco users go through or with every other drug.
I for instance, after doing pack a day of cigarettes for over a decade, after I stopped smoking I felt like shit 3-4 month with headaches, mood and blood pressure swings.. eventually it normalized.
if you are a heavy MJ smoker for several years who is trying to stop smoking, get ready for a wild ride as it will hold you by the balls and squeeze 'em hard so to speak
yeah it's not physically addictive though but it is a mind-screwing experience or unscrewing )
anything is good in moderation, mostly anything.
if you can't go on without something - that an addition, it's an issue of being weak, except for some rare medical conditions.