I Went To Toilet To Urinate Suddenly Had This Massive

I went to toilet to urinate suddenly had this massive pressure and stabbing pain I went to bed but couldn't do anything for the pain was too much I took some pain killers went to toilet passed a normal soft stool and went to sit on sofa the pain is still in lower abdomen and bum and it feels like swelling on stomache in center and to right but I'm overweight and had a few operations so could just be scar tissue the pain isn't as bad if I slouch on sofa I can't sit up or move a out as too painful what can this be I have pcos bug never had this pain before. I don't think it's relevant but my Nipples are really sore
Aswell which I've never had before