I been on my depo shot sense feb.2010. I always had my period a month before I had my shot. Well this time my shot was due in jan.2011 and in dec.2010 I didn't have my period.. Is that normal? I still haven't had my depo shot and still haven't had my period but when I take the test it say negative.. What could be going on? I been having headaces,and lower stomach pain.. What could it be?