I have been placed on the Depo Vera shot and my next shot is coming up within the next few days.

What I'm curious is last month I did have my period - October 3rd. and this month, Nov. 3rd, I had my period on time but two weeks later I've started spotting and then having a normal flow, this goes back and forth for about two days now. During the week from October 3rd - 7th I had a normal flow also I had sex for the first time and protection was used - I'm very cautious even if I'm on birth control. I had my period this month - Nov. 3rd - 7th but I started spotting two days ago and I'm not sure as to why.

I do have a few medical problems such as polycystic ovarian syndrome and a tipped uterus so my periods have always been random - until I was put on the shot - and always very very painful so the spotting was something new but it also felt like a normal period. I'm just wondering why the second time in the same month of November. Could this be the sign of a pregnancy or something else?