Thanks for the query to H.C.M. Forum.
is a medroxy-progesterone
hormone and it don't causes any abnormalities in menses .
As you mentioned that period is from 10 days although light in nature.
Last month there was no period as you mentioned that only there was spotting.
This is an indication of irregular bleeding or dysfunctional uterine bleeding
In my opinion get in ultrasound
of uterus as well both ovaries for any disease .
Consult a gynecologist and get his opinion.
Good luck. Dr. HET