Hi. I ve gone through your query and I can understand your anxiety. Depo-Provera shots are very effective in preventing pregnancy (99%). These injection is a long-acting birth control method. As it is a hormonal birth control shot, its effect on menstrual cycle might vary from missing menstrual periods to breakthrough bleeding, spotting etc. Common Side Effects of Depo-Provera shots include acne, dizziness, drowsiness, fever, headache, hot flashes, nausea, nervousness, pain, redness, or swelling at the injection site, sleeplessness, or weakness. So your symptoms might be due to the shot. If the symptoms are troublesome, consult your nearby gynaecologist. Hope I have answered your query. Let me know if I can assist you further. Take care. Regards, Dr. Yogapriya V, General and family physician.