I keep havin a sharp stabby pain in or just under my belly button area, it's really unpleasent, it feels like really bad stitch in that area, hurts more when I bend in a particular way and when I sometimes stand up, jut to add I am on my lovely monthly cycle so I have got the normal period pains too, I've had this before maybe 2 months ago but I wasn't on my period at that time, any ideas on what this could be