Need an expert's opinion...

Hi. Last cycle I found out I was pregnant. Shortly after I got odd sensations behind my bellybutton, and an odd rash (I later learned was vasculitis) Within days of the tummy sensations I miscarried. The tummy sensations lasted about a week and the rash faded away. A month later again the rash and odd tummy feelings came back, and I thought I must be pregnant again as I had never felt this feeling before. Nope. Turned out to be appendicitis, I had an emergency appendectomy a week ago. My question is, this feeling behind the belly button was very different from anything I've ever felt. I've read that appendicitis CAN cause miscarriage. I am hoping this was the cause, as the problem is "gone". How common is it for appendicitis to cause a miscarriage? P.S. the rash is fading since surgery-I think it was related. I also have PCOS and lupus (negative for APS and anticardiolipin antibodies)