My period was over 2 weeks late last month and ony lasted one day but it was very light. tests still neg. could i be pregnant still?

Pregnancy unlikely: A urine pregnancy test, done correctly, gives a reliable result 3 weeks after sex (3 weeks after when conception might have occurred), 1 week after missing a period, or 1 week after starting a "weird" period. If done sooner, a positive result is likely real, but a negative result may be due to testing too soon, and thus lead to a repeat test.

Reliable: urine home pregnancy tests are reliable and when negative, the presence of a pregnancy is highly unlikely. To be more certain, pregnancy hormone levels in the woman's blood can be tested.