The obvious answer; having sex which caused a pregnancy. Plus many other life events: BCPs, stress, dieting, change in your exercise routine, illness, weight loss.
Nope anti-depressants shouldn't effect your period cycle.
No, humping a pillow doesn't effect your period. Your period is controlled by your menstrual cycles, masturbation has no effect on this what-so-ever.
No, your period has no effect on your pulse.
No it shouldn't effect your period -
A longer pendulum has a longer period.
no
Yes, it can be If you are on your cycle and you start having gas, it a very common sign that you are starting a period
No. There is a period of time before menstruation begins when sexual activity can stimulate the release of an egg (in effect, starting the menstrual cycle). If you are having sex, you should always use a condom, regardless of your age or stage of sexual development.
You can.
The mass has no significant effect on the period.
Starting the pill before your period may delay your period, but you may also have breakthrough bleeding during the first three cycles. If starting the pill before your period, use a back up Birth Control method for the first seven days.
no