Thanks for posting your query.
Normally ovulation or egg release happens 2 weeks prior to your next period.
If your cycle length is 28 days it will be around 14th day but not always.
You had unprotected sex on day 6.
Chances of pregnancy are less with that single exposure but we cannot be absolutely sure.
We need more details on your cycle length, how was the flow in april periods, and any unprotected sex after april 10th .
In any case , a blood test
is better than a urine test if you want to check for pregnancy now.
The symptoms of nausea, vaginal discharge
and swollen breasts are non specific.
They are due to the effects of hormone progesterone
which gets secreted prior to your periods and also in pregnancy.
The slight bleeding could be due to hormone disturbance or a problem in your cerrvix/uterus/vagina.
Apart from testing for pregnancy, its important that you meet a gynaecologist who will check you and find out the reason for this out of schedule bleeding.
Its also advisable to go on a reliable method of contraception
to avoid this situation in the future.
You can also schedule an appointment for pap smear
and enquire about having HPV vaccine
to prevent cervical cancer
Hope this has helped.
All the best, take care