Last sex nov 12, had light period lasted for 4 days nov 25, jan 7 now 5 days delay, am i pregnant?

Maybe not, but...: If worried, just do a pregnancy test. A urine test done correctly gives a reliable result 3 weeks after sex (3 weeks after when conception might have happened). If done sooner, a positive result is likely real, but a negative result may be due to testing too soon, and therefore lead to a repeat test. If a woman has her normal regular period, then she is not pregnant, and a test is not needed.