irregular period

Im irregular to my period . How can I start to count? January 12 is my first period and FEBRUARY , MARCH , APRIL I dont have a means that months and I decide to take a pregnancy test and the results is negative. The month of MAY I have a symptoms of pregnancy and the whole months of MAY I dont have a means . JUNE 2 I decide again to take a pregnancy test and the results it positive. So which month I start to count ?