TTC a little worried

Hi... I was a teen mom of 1. My daughter is 6 years old now and I had her emergency c-section. I recently got my depo shot in Feb 21st of 2016. I was supposed get my 2nd shot in May 22nd of 2016 during those 3 months in the depo shot I been having my period, long heavy periods. then 1 month break and now I got my period for 5 day not so heavy as usual before the depo shot. As of July 2nd was my 1st day of my period and ended on the 6th 2016. On July 13 I released a white discharge size of a dime and I was having right pelvis pain. I been having unprotected sex this whole time... today is July 19th and I been having lower back pains and pelvis pain just mild pain and I also been spotting, today is day 2. Every time I wipe there's pinkish on the toilet paper or on my underwear but not in the toilet. No I see pink discharge. I feel like if I'm starting my period again... I been trying to TTC... is this a sign of pregnancy? I'm sad because people say I have no chance due to the birth control method I used. I have been moody lately. I hope this couldd be a possible pregnancy..