Injuries!
It's not just the 'what' that had been forcefully taken, but the use of the term 'injuries' to describe it clearly indicated Liu Shimei's confidence in the dosage of the drug she had administered.
Zhang Qingxi was already a despicable person, known for his mistreatment of countless young women. With his actions now controlled by the drug, it's doubtful that he would show any kindness or consideration towards Liu Yan'er.
As for Madame Zhang's disheveled appearance, it was likely a result of the torment Liu Yan'er had endured. The pain had probably driven her to take out her frustration on Madame Zhang.
Both mother and daughter seemed to have lost their sanity at this point.