your bleeding after intercourse
could be post coital bleeding, white discharge usually increases during intercourse,
as you are having irregular periods
it is difficult to estimate the time of ovulation, if you are having previous episodes of unprotected intercourse
then there is possibility for pregnancy, or if only on 25th, then this much early we cannot detect pregnancy,
your scanty flow can be menstrual flow only as menstrual flow can vary depending on many factors like anemia, hormonal influence etc,
so you better wait for 2 more weeks and go for blood test
for pregnancy to rule out the possibility.