Hallow Dear, Depo Provera is long acting slow release Progesterone preparation. It should not give any symptoms like headache, aches, malaise or weakness, particularly 4 hours after the injection. It seems that you are having flu or such viral infection. You need to take some antipyretic painkiller like Paracetamol. Steam inhalations will give you some symptomatic relief. It is advisable to take hot drinks, in particular hot soups. Ginger powder mixed with jaggery in hot milk is good in such symptoms. Hope this helps you. Dr. Nishikant Shrotri