Not sure if you're trying to get pregnant or not since you posted this in the pregnancy category.
But if you're trying to get pregnant then the spotting can mean that you're pregnant.
The spotting and discharge of blood from the vagina usually means that the egg has fertilized and conception has occurred.
Having light bleeding, or spotting, during your pregnancy is very common, especially during the first trimester of your pregnancy.
However if you're not trying to get pregnant then yes Stress can indeed cause spotting and is usually not a cause for alarm.