Hello,
thanks for using health care magic.
The symptoms you have listed above could be explained
by the pre-menstrual syndrome which is a collection of
symptoms occurring on the second half of the menstrual
cycle.
Day 11 and 17 are at the extremes of the fertile period
of a 28 day cycle and chances of being pregnant is low
but possible to have had a
pregnancy.
However, pregnancy test has an appreciable negative
result only after after the expected date of menses.
So the pregnancy test which you did on the 26th day of
your your cycle is hardly conclusive.
Spotting on its own associated with a delay in menses
and abdominal pains are a collection of symptoms that
require immediate investigation.
You should consider seeing your doctor and for at least
an
ultrasound.
Best regards.
Dr Achuo