If you have changed over to the pill only during this cycle, do not worry. It is common for such spotting to be observed as the body adjusts to the new hormonal
milieu. It is a breakthrough bleed. You should usually receive a period in the next cycle and if not, please go ahead with pregnancy
tests. Weight as proportionate to the dosage of the hormone has an effect on the menstrual pattern and it is essential to bear in mind that a healthy weight is necessary for proper function. Hope this helps.