What Causes Irregular Periods And Abdominal Pain?

Hi. My period cycle usually alternates each month. One month it s 28 day. The next month it is 30 day. This month was meant to be a 28 day cycle. My period was late. I did a number of pregnancy tests but they were all negative. My period came on day 36. It has never been this late. On the day my period arrived I got a pain in my upper right abdomen. It s been over 24 hours and its not going away. Could the 2 things be linked? Should I speak to my doctor about it?