What Causes Light Spotting , Cramps And Headache?

I have just finished my period, (yesterday) but now have light spotting and bad cramping as though it's just about to start. I also feel very bloated and have a hard line (not muscle) length ways across my lower abdomen behind a scar I have from an ovarian cyst removal from 15 yrs ago. The last time I felt that was in the summer when I was pregnant with twins, (but miscarried at 12 weeks). I'm having random headaches and am so tired all the time. What is wrong with me???