hi i had gone through your query and understand your concerns.
-wait for another four days,and repeat the test again.
-if the second time also negative,kindly rule out the possible underlying for infertility
the possible causes for infertility for women are;
;increased TSH levels in your blood confirm the diagnosis.
-PCOD;poly cystic ovarian disease;due ANDROGENS the ovum cant be releasedultrasound
scanning for pelvis may confirm the diagnosis.
-hyper prolaction in your blood are some causes
sometimes stress may prevent the pregnancy
without any underlying pathology.
I hope this is helpful for you, thank you