Hi thanks for your question.
There could be few reasons for this spotting. First being the early return of your menstrual cycle, this could be irregular in the begnining. Second reason could be cervicitis
that is inflammation of the cervix
. Third could be infection of vagina, what is called as vaginitis
. Consult a physician who examine you to rule out/ confirm cervicitis or vaginitis as a cause for spotting and may treat accordingly.
Hope this answers your question