Hi,
Thanks for posting in HCM.
I understand your concern.
Pre-ejaculatory fluid may contain sperm, which can make a woman pregnant, even when full ejaculation doesn't occur within the vagina.
However, the chances is very less as the possibility of sperms travelling quite a distance to fertilize egg is remote.
In case you wanted to prevent
pregnancy from happening, you should have used
emergency contraceptive pill or morning-after pill, within 72 hours following the act.
Otherwise, there are no other medication available to prevent pregnancy by inducing
menstruation at this time.
It would be advisable to wait for your periods to happen normally.
Alternatively, you may take a urine pregnancy test and consult Gynecologist to review your condition and then prescribe medication to induce menstruation, accordingly.
Hope the information provided would be helpful.
All the best.