I Think I May Be Pregnant. I Had Sex Around

i think i may be pregnant. i had sex around 2 weeks ago on a saturday. i went to the clinic to get the morning after pill on the monday as all clinics were closed on the sunday. i was given contraception in the form of a patch. i started taking them but took it off after 3 days because of migraines. i had been gettin period like pains for a couple of days and i have noticed brown light period. i was told to take a test on the 31st october just to be sure. but does this mean im pregnant or is it just a period?