thats a mental addiction, cannabis does not cause physical addiction and ANYTHING can cause mental addiction and I do mean anything- sex, TV, jacking off, etc. once your mind gets something every day for awhile It starts to think it needs it. My advice is to do whatever it takes to keep your mind off it, I usually play with my pets, draw, or do some school work works for me

EDIT: to answer your question yes I have felt that way many times but I welcome that feeling anyday comparitavly to actual physical withdrawal -.- that sucks 10 fold lol