Thanks for the query.
The possible causes of blood in the stool are anal fissure
etc. that can occur due to constipation
If you noticed the blood from the vagina, the causes could be:
-As your cycle length is short there is possibility of implantation
-Sometimes around the period of ovulation also minimal spotting can be seen.
So you wait till your expected date of periods and if you miss the periods, go for pregnancy
For more details you can ask me through: http://www.healthcaremagic.com/doctors/dr-sree-gouri-sr/63429