I have smoked pot on and off for two years now -- one or twice a month. However, in the previous month, i have used it several times a week, sometimes, once or twice a day. I have decided to quit because my teeth became noticeably yellower, my throat hurt, and I coughed up phlegm. So far I have been successful. My thought and teeth are much better. I am exercising, eating good food, and trying to keep a positive attitude. I am even keeping a journal to keep track of my thoughts and try to deter myself if I get a temptation to smoke again. I suffered from suicidal depression last year (unrelated to marijuana consumption), and two days ago, I felt depressed to the point of hysterical crying for the first time in more than a year. This depression has since faded. But my biggest concern is my inability to reach a full erection. I can achieve a full erection by masturbating (forgive my frankness), but I cannot achieve one by the conventional means (that is, sex or forplay). This is incredibly frightening seeing as I am only 18 years old. Is it possible that marijuana withdrawals could produce this inability? And when these effects subside?