Pregnancy needs sperm to reach the vagina, and fingering without ejaculation carries a very low risk, since precum rarely carries enough live sperm to cause pregnancy this way. The period that followed within 7 to 8 days, even if lighter than usual, also points away from pregnancy.
Next Steps
A lighter, shorter flow can happen from stress or the normal hormonal shifts around ovulation, so it doesn't need to worry you on its own. If you want extra reassurance, a home
pregnancy test next month is a simple way to confirm.
Health Tips
If your next period doesn't come as expected, or the light bleeding continues beyond a few days, please see a gynaecologist.