What test is the best???

I AM 28 DAYS LATE FOR MY PERIOD... I KNOW YOU GIRLS ARE GONNA SAY GO TO THE DOCTOR.. BUT I WANT TO WAIT UNTIL THIS MONTH IS OVER... I USUALLY GET MY PERIOD THE 27 SO IF I DONT GET IT ILL GO TO THE DOCTOR... MY QUESTION IS WHAT BRAND IS BETTER TO TAKE WHEN YOU ARE THIS LATE???