Hello
if there is missed periods and you have checked with strips and it didn't show positive then there are two condition
1. Do not have pregnancy but may it delayed periods. In this case wait and watch it will comes.
2. if you are
pregnant but strip now shown any line then you should have to try after 2-3 days once. still it not positive then you should have to consult gynec and confirm with sonogrpahy.
in both cases you should have to wait for at least 1 week.
Regards,
Dr. Nikul Patel
Ayurveda consultant
Ayurveda Gynecologist
Ahmedabad
Whtasapp - +91-98250-40844