Thank you for your query.
The easiest way to know if you are pregnant is to take a pregnancy
test, so please do that at the earliest.
Also, the breast tenderness is most probably due to the wearing off of the Depo shot.
It is a hormonal
preparation, and once you are off it , after using it for 3 - 4 years, your body adjusts to the hormonal changes.
The pinkish spotting
also could be most probably due to this.
Your body would take 3 months atleast to adapt to the weaning of the Depo.
Meanwhile, if you are not planning a pregnancy, you would do well to have protected sex.