Starting to have a LOT of issues with my adopted son

We adopted twins at the age of 4. They were placed in my home through foster care at the age of 18 months. They are now just turning 7. We have had learning issues, language issues, social issues, behavior issues, etc. Both were put through services early for learning development and speech. They are now in 1st grade and doing ok academically. Both have an IEP and are still in speech once a week. My son has always been about 6 months to a year behind his sister in about every aspect but can also do a lot of things that his sister can not but he has been more of a challenge with most everything which has caused a lot of anxiety in the house. I can go on and on with all of the problems we have faced and the solutions we have tried. We actually called another IEP recently to have him tested for an array of other possible problems that may be causing these behaviors. But now there is another one. He is now continuing to have BM's in his pants. Although in the beginning we did give him the benefit of the doubt thinking he had tummy problems but now Its obvious he is doing it to get the reaction/attention. Today was just it for me and I had a melt down(not in front of him). Basically I went to wake him for school and the smell hit me when I opened the door...he was just laying there in his own poo waiting for me to open the door. My husband handled it so I could ready the other kids. Basically without emotion while having him clean himself up. He went to school. We got a call before noon. For the first time he did it at school. Something we never thought he would do because he seems to act embarrassed to let the other kids here at home know or see him like this...its always seemed to be just for mine and my husbands benefit. I have just gotten so tired at this point and I need to know that there are others out there that have been through this, have lived it. How did you deal with it...did it ever get better?? I feel like I am at the end of my rope...