What will happen to me when i come of the contraceptive injection?

has anyone came off the depo- provera injection and what happened when you come off it? ok so i have been on the injection for over a year and i have put on a stone with it which is making me feel depressed so i decided to come off it. i am due my next injection in a few weeks so i am not going to go for it. when i read up about the injection making m put on weight it said it can cause tiredness, depression, mood swings, loss of sex drive and weight gain. i have experienced all of these things but i didn't realise it was because of the injection i thought it was just after having the baby it was my hormones. i have also read that it is used to chemically castrate sex offenders :/ so i also read about the side effects you have when you come off the injection and it says mood swings, depression, crying all the time at nothing, hard to lose the weight you put on with it and irregular periods along with other things. how did you find coming off it and did you experience any of these symptoms. also how long with it take for it to leave my system.