needing some advice about my step daughter

okay pretty long story but to shorten it up I'll sum it up we recently got custody we have had them since mid June their mother dropped them off saying she was done she wanted them to live with us. few days later my 5 yr old step daughter in very much great detail told me that her moms bfs kids raped her (not her words she said what happened) we reported it and got an op so her mom couldn't come back and get them. we filed for Sol custody it didn't make it that far she agreed to the op and to give us the kids and no longer have to pay child support and she was granted supervised visitation twice a month and 6 hours a day. every since the first visit she has acted out the two year old not so much but my step daughter it is getting extreme she's not behaving in school or at home and just acts like she doesn't care I cannot legally take away her visits with her Mom. we have enrolled her in counseling but hasn't started yet well in the past couple days she's had started something new. when we get on to her it sets her off. today I told her not to lock the puppy in her room next thing I know I hear the baby gate latch so I go in there and tell her I already warned you you are now going to time out( we use a scale with her and she had already gotten in trouble for not listening) told her she had to sit in her bed. her 5 mins was up so I go to talk to her about it and she had chewed her cheeks and made herself bleed and spit in on her bed and was playing in the blood. when I asked her why she did it she told me because she was mad. her dad heard me ask why she was bleeding and came in the room and asked her why she told him its what my mommy does when she's mad she makes her self bleed with a knife. I hadn't notice it before but when I was stripping her bedding to wash it after that it apparently was not the first time I found 4 blood spots. (she makes her bed every morning before school) idk what to do about this. I tried to tell her she's seeking the wrong kind of attention she wants good attention not bad idk I'm so confused and scared and worried.