Welcome to HCM forum..
As u have stated that now u r past 5 days of ur cycle, most common cause of this is pregnancy
.. Ur home pregnancy test checks urine HCG, levels of which gradually increases, usually positive after one week.. So kindly repeat the test after 3 or 4 days.. If its still negative, consult to ur gynecologist soon as they can check HCG level in your blood and confirm ur pregnancy.. Please donot neglect.. If U r planning for abotion, it is better to get it done asap..
There are other causes like fibroid uterus
.. Its always better to ruleout all these illness, which are also treatable.. So u need not panic.. We are there to help you.. Get back to us if u have further queries..