My period is usaly regular and it should have come 2 days back neg pregnancy test done my cycle is 27-28 days had breakthrew bleed on he second help?

Anovulatory bleeding: Pregnancy is always on the list of possibilities when a woman has abnormal uterine bleeding or cycles. You may be having anovulatory cycles (cycle without producing an egg from the ovary). If a urine pregnancy test is negative, i would recommend evaluation by your gynecologist, and treatment will depend on the cause of the abnormal bleeding and your current short-term pregnancy goals.

Need to repeat test: You may wish to re do the home pregnancy test when you are 4-5 days past the due date for your period. Use first morning urine and follow the test instructions carefully. If you miss more than one period, it would be prudent to see your doctor.