i am 22years old and unmarried. i had sex with my boyfriend on October 1...
i usually have 27-29 days circle...and my periods was due on october 1...
but i did not get it then instead i got it on october 6.

i usually get to have a drop of blood, just like a thin strand along with white discharge. i got the same on october 3rd.but my periods did not start the next day. it was followed by the same kind of white discharge for the next 3 days.
i did a pregnency test but the result was negative.e bleeding just like my periods.

the very next day oct 6, i got my periods....the blood flow seemed to b normal. it lasted for 6 days. i had sex on the very next day.i took I-Pill 72 after sex. i took the pill for the 1st time. i felt too tired, sleepy and also nauseous.it lasted for 2 days.

we then made love yesterday morning.i found blood on my panties yesterday evening, but it did not last long. now today i have bleeding just like my periods.

may i know the possible reasons for this.
is it normal to have periods twice a month... that too wit 15 days gap.
are there chances of me getting pregnant.
the climate here was too hot previously but since last 3 days its raining here heavily. can the climate bring such an affect?
i even had had lot of papaya, pine apple and a sweet made of sesame seeds last week as i dint have much bleeding..but i stopped it once my bleeding got normal

i still had papaya and pine apple juice and also the sweet made up of sesame seeds after my periods.

can someone please let me know the possible causes