Period 8 days late no pregnancy symptoms and negative test. Could I be pregnant?

If you had sex than yes. Some women don't get symptoms for awhile, or at all (my sisters only symptom her first pregnancy was a growing belly, and barely that). You'd still be very early in the pregnancy. And it takes some women a month or longer after their missed period to get a positive hpt. To find out you can either wait until your next period is due and take another test or you could go and get a blood test done.

Am 8 days late,I have a water infection,feel sick,lower back ache,heartburn but 6 negative tests