pregnant? or it is just effects of first-time sex?

Hi,
Welcome to ehealthforum,
If you had been sexually active without protection after finishing with periods (close to your ovulation time), chances of pregnancy are possible. Pullout/withdrawal method is associated with highest failures (pre-cum/pre-ejaculatory fluid is known to contain sperms and no man can be 100% sure that pre-cum/pre-ejaculatory fluid did not leak out during vaginal penetration). The symptoms of lighter periods, brown discharge, headaches, could be few of early symptoms suggestive of pregnancy. Look out for development of any other new symptoms if pregnancy is suspected. If periods have not started within 10 days of expected period dates, or if you have got abnormal periods, or if you suspect chances of pregnancy, consider visiting your doctor/gynecologist at the earliest for thorough examination (to confirm pregnancy related changes/signs in body) and blood/serum HCG level test (to confirm/rule out pregnancy accurately). If pregnancy gets ruled out, and if you are not ready for pregnancy, but intend to remain sexually active, you should consider visiting your gynecologist to get started on suitable regular birth control measures to be protected (after your periods). Be regular with birth control use as instructed. Avoid having unprotected sexual contact if you are not ready for pregnancy.
Take care.

Actually during the days of which I expect to have my menstruation there's a blood came but I'm not really sure if it was really brown purely but there is really a blood I assure you. Basically, the blood thing came exactly on the date of my menstruation only that it was not a bit heavy. I describe the blood flow as not so heavy like, like my menstruation is about to end wherein. For the first day, it was ok I consummed one pad only and the next day, 1/4 of the pad was only consummed so as the next day, on the fourth day which is today, only ample amount is coming. I normally have headaches when my menstruation is coming so, I'm really just confused whether what's going on now is my period or what. I don't feel any changes, my breast is not swollen. I just thought that I'm panicking. . I don't know. Could you please help me figure this thing out?