Missed period and negative home pregnancy
If you period is late and you have a negative pregnancy test there are many things that can be going on. You might have had an irregular cycle month and have a really long cycle for some reason, this is usually caused by late ovulation. Some women might have a hormone imbalance or have a medical condition causing them to have an irregular period. It is possible that you ovulated late and might be pregnant but not pregnant enough to get a positive test yet.
Wait a few days or a week and then test again. If you test is still negative and your period has not come yet you should consider contacting your doctor.