I had a baby 14 weeks ago, and got the depo injection 4/5 weeks ago but I had unprotected sex before and after. I took two tests before getting the injection and they were negative. I decided on the depo injection as I had it before and never had a period. I thought I had started my period yesterday and last night I had terrible cramp and felt sick and when I woke up there was a blood clot on my pad (which had never happened in previous periods). So I'm worried it might have been a miscarriage and not a blood clot.