Feeling sick? :(

So about a couple months ago I wanted to know what it felt like to masturbate because I never have before...
I grabbed two objects & put them in both my vagina & anus at the same time. Although I strongly regret it because now I get pains in my stomach constantly... In the beginning I had a brownish discharge coming out of my vagina & It looked & smelt like poop... although that doesn't happen anymore... But when I have a bowel movement for the first time after doing that... It was black & hard to push out. . .
I went to a doctor but I'm really scared to tell him my reason to what may be causing this pain... So I left out the awkward part & just brought up the pain. . . He took an X-ray & told me everything was working fine... He even took a blood test & a urine test... But everything came back fine.
I'm just really scared. I get pains in my lower left side by my hip bone sometimes I even get pain in my right side of my chest...
I want to go back to the doctor but I'm so nervous Please if anyone has an idea of what's going on please help me! What do you think might be wrong with me?