UPDATE ON MY 2day late cycle

OK SO I WENT TO THE HEALTH CLINIC TODAY BECAUSE MY CYCLE IS OFFICIALLY 3days late. WeLL SHE SAID TECHNICALLY MY CYCLE ISNT LATE AND IT SEEMS THAT IM STRESSING.(4th negative test btw) 3home and one at the clinic. AS I TOLD HER MY CYCLE IS NORMALLY ON TIME IVE BEEN 1day late before but never 3. Experiencing some stomach cramps, lower backache, constipation, and mood swings as my cycle is approaching, but its not. Theres no sign of it at all. Only the symptoms that are associated with early pregnancy which are easy to confuse with a cycle. Hmmm what do you guys think. 3rd opinion anyone?