N 2009 I Had A C Section And Tubal Clamps

n 2009 i had a c section and tubal clamps always had regular periods until now. I'm 6 days late took hpt but negative(also didn't use first morning urine) have been very nauseated, slight but constant pain lower left abdomen(started Jan. 20th), fatigue, mood swings. Ovulated on the 12th, spotted on 19th, period due 26th.