Hi,
Thanks for the query.
The possibility of
pregnancy is less in your case.
Because usually in case of regular periods ovum will not release on around 6th or 7th day.
The symptoms you had could be due to ovulation.
Which is also called
mittelschmerz syndrome.
Refer: http://srsree.blogspot.in/2012/08/mittelschmerz.html
If the symptoms persist better to consult gynecologist once.
For more details you can ask me through: http://www.healthcaremagic.com/doctors/dr-sree-gouri-sr/63429
Take care.