shorter periods

I was on lutera for almost a year and my insurance kicked in so I went to the pharmacy and they gave me the generic brand of lutera which is Sronyx. Since I have been on Syronx for the past three months, my periods are coming on the same day each month but they are very short and i am not really bleeding a lot at all. I will get my period for a day or a day and a half. it doesn't last any longer than that with Sronyx. Is this unhealthy for my body to be having such short periods each month with barely any bleeding. Should I switch back to Lutera where my periods lasted for about 3 days. What do you recommend?