Depo-Provera

I have been on birth control most of my adult life, I am 41 years old. I stopped taking the pill 2 years ago because my system was so messed up as I went to the "3 month pill" where I wasn`t supposed to have a period for 3 months. Didn`t work, so I stopped for 2 years and my body got back to normal. Just 6 weeks ago I started the Depo shot. I have been bleeding for 30 days now and it`s getting worse. I`ve gained about 5 lbs and have bad headaches, chronic abdominal pain and bloating and mood swings. I have trouble sleeping and am always tired. I don`t know if this is from the shot, but I don`t think I`m going to take the 2nd one. It`s not worth it.