Can i be pregnant even if a home pregnancy test was negative?

Maybe: If you have regular periods and if you tested sufficiently late in the cycle, it wouldn't be very likely because the tests are mostly reliable. Otoh if you tested early or cycles are unpredictable it's definitely a chance. I'd suggest testing again in a day or two before taking too many other steps.

Depends: A negative pregnancy test done too early does not rule out pregnancy. If you had sex since your last period, and missed your period by 4-5 days, do a home pregnancy test. If the result is negative repeat the test 4-5 days later unless you get a period by then. Use first morning urine and follow the instructions for the test carefully. You may get get a blood test one day after missed period.