I'm four days late with my period and having all of the symptoms of pregnancy but im still getting negative test results could I still be pregnant?

Blood test. A quantitative HCG level from a blood test could be positive even when the home urine test is negative.
Yes, could be. Urine pregnancy test may not become positive till a week after the first missed period. You should repeat the test in 4-5 days or you may see your doctor for a blood test that is more sensitive.