Is Spotting After Unprotected Sex And Stress A Normal Response, Or Could It Indicate Pregnancy?

Hi! I had sex 10 days ago. On June 23, it s supposed to be my period. But i only have spotting until now (June 25), after the unprotected sex i was so stress because i am worrying a lot if i will get pregnant, but it is withdrawal. Is this normal? Is this only because of stress?