Irregular or abnormal menstrual bleeding can occur due to many reason like hormonal imbalances, stress, changes in contraceptive methods, etc. It doesn't always mean that its about pregnancy. If you are concerned about the possibility of pregnancy, it's advisable to take a pregnancy test to get a clearer understanding of your situation. 

It is possible that the bleeding you experienced was implantation bleeding, which can occur when a fertilized egg implants in the uterus. This can sometimes be mistaken for a light period. However, it's also possible that the bleeding was due to other factors. If you have concerns about your menstrual cycle or possible pregnancy, it's best to consult with a healthcare professional.

Pregnancy symptoms close to ovulation might be unobtrusive and the period is different. Here are a few possibilities:

Implantation bleeding (6-12 DPO): Just a light spot or pinkish colour, lighter than when you get your period.
Breast tenderness/changes (7-10 DPO): Tingling, swelling, or increased sensitivity.
Fatigue (any time): Progesterone surge can cause exhaustion.
Nausea/food aversions (later in first trimester): May not appear this early.
Remember, these can be PMS symptoms too. The most reliable indicator is a missed period. 10 to 14 days after ovulation take a home test for accurate confirmation