
Bad temper, angry, headaches, nausea, irritibaility and similar are common. These are, of course, symptoms of depression too but the difference is that
after quitting smoking these effects abate quickly after a couple of weeks.
Not so with depression and it does not come and go with one's decision to smoke or not to smoke. That is simply an infividual's reading of what is going on for them.
By the way, I smoked for 35 years and gave it up 2.5 years ago with no support. Just decided to stop.