What Causes Delay In Periods And Lower Abdominal Pain?

my name is brandy I live in Ms.Here the whole story. I was pg in 2006 had a miss with twins did not have insurance so a dnc was not done but i was only 3 mnths. Well shortly after that my pms stopped. I have not had one in 2 years untile 3 mnths ago brown tissue started coming out on the 7th every mnth it has done that for 3 mnths except this mnth I was 2 days late i started the 9th still brown stuff. Then I took 2 pg test this week one was positive and the other negative I took them one day apart. My lower and upper right ubdominal hurts all the time exspecally if i stand up for a period of time. ppls help me