Could my pregnancy test be negative?

An early pregnancy test might pick up very low amounts of hCG. However, it's possible that you don't have enough circulating hCG to get a positive result even on a sensitive test. Another common reason for getting a false negative is not having enough hCG in the urine you test.

Yes, obviously.  Yes, the test you took is negative. Your symptoms are PMS symptoms not symptoms normally associated with early pregnancy. 

If you've had unprotected sex since your last period, it is possible that you could be pregnant.  All home pregnancy tests look for the hCG hormone.  If you test to early -- even with a more sensitive test -- it is very possible that there won't be enough hCG in your urine to show up.  The best option you have is to wait another 4-45 days and test again if your period hasn't started.  

It’s still early so a negative test is possible. Wait until you’re about 1 week late. But from the symptoms you listed above, it sounds like you’re experiencing PMS

Obviously, since your test WAS negative, it certainly CAN be negative.

Headaches don't mean you're pregnant.

 Cramps don't mean you're pregnant.

White discharge doesn't mean you're pregnant.

Test again in a few days if your period is still late.

Dehydration. Drink plenty of water