Recently I've Been Dealing With Stomach Pain, But Only When

Recently I've been dealing with stomach pain, but only when I stand up when I'm sitting or laying down it goes away , that has been fading away but no there are times my stomach pain begins, it feel like butterflies but I'm not nervous or worried , then my upper stomach pain begins and now I feel pressure in my head and my back had started to hurt, I don't get my period anymore , due to depo shots I get ?