My daughter is 12 years old and was diagnosed late last year with...

My daughter is 12 years old and was diagnosed late last year with exercise and/or stress induced asthma. She had a severe asthma attack at school. I was hesitant about taking her to the ped, as she had never had an attack before. She has always had allergy problems, I guess it is typical to where we live. The pediatrician put her on singulair and she uses a rescue inhaler, ProAir. The doc gave me a months worth of sample tabs to give to her to see if it would improve her wheezing and coughing. IT WORKED! The tabs they gave me were 10mgs. Because it was all new to us, sometimes we missed a dose or two, but her symptoms improved, but she also experienced headaches, nausea, complained of her mouth hurting, especially in the mornings and she couldn't sleep (these symptoms we noticed after seven days of being on the meds). I read the pamphlet for side affects and these were typical side affects, not to be alarmed right? By the time we made it through the all the tabs she started with some behaviors you might expect to be normal for pre-teens and some that were alarming. Most parents know their children very well, especially behaviors. My pre-treen was a very loving and agreeable child and never had outbursts of anger that was uncalled for. To make a long story short, I didn't fill the prescription because of the above stated behaviors. Within about eight days, my child was back, but so was the wheezing and the coughing and the picking her up from school three times a week because of her asthma, so back to the doctor we went again. They wrote the prescription for singulair 10mgs and I got it filled. A very interesting thing happened when I went and filled the prescription. The pharmacist told me that the doctor was prescribing too high of a dose for my child, that the 10mg dose is usually given to adults and not children. So I cut the tabs in half and started her back on the meds. She has been on them for almost three weeks now and it has of course helped the wheezing and the coughing but we are back to not sleeping, angry outbursts (probably from not sleeping) and not wanting to go anywhere or do anything with her family or friends. When I saw the news about singulair it really scared me, because I love my child and I don't want anything bad to happen to her. I called the doctors office, our doctor was out, the nurse said for me to not give her the meds for the rest of weekend until I can talk to her doctor on Monday. I will update you all of what our pediatrician has to say.