How Can diarrhea And Stomach Pain Along With Headache Be Treated?

Hello I have a 10 yr old daughter and 6 weeks ago she complained about her stomach hurting and was having diarrhea, head hurting, and very tired. I took her to the doctor and they said there was nothing they could do for her stomach, took blood sample (everything came back ok with blood) and send me out of there saying she had walking pneumonia. We got antibotics and steriods at the pharmacy and I picked up a bottle of imodium ad. About a week or so later the diarrhea stopped, but she was still having very soft stool and she wasn t making to the bathroom in time. She has never had this problem and now 6 weeks later she is still having accidents and cant make it to the bathroom in time. She complains her stomach is hurting. Her stool is still soft and she hasnt had a normal hard poop since this all started. Please help.