Hi welcome to healthcaremagic Forum
you have just passed 5 days of ovulation., this doesn't indicate
pregnancy..
Amenorrhea is the first sign of pregnancy.. UPT ( urine pregnancy test ) is the test done to detect pregnancy.. it is an antigen-antibody test.. it will be positive minimum 3 days after conception... finally you must confirm the pregnancy by USG scanning. there are many reasons for dark brownish stools.. but
loose motion or brown motion is nor related to pregnancy..