Rhe symptoms and conditions

Last Tuesday, my son was prescribed Singulair by our pediatrician. He was also prescribed Pulmicort by nebulizer at the same time. Within a couple of days, I was noticing a dramatic change in his personality. He's only 21 months old and normally a very happy, lovable, easygoing little boy. He did a complete 360. By Friday, I had to take a day off from work, as I was too scared to send him to daycare. He took his last Singulair chewable tablet on Friday night. Saturday was his worst day by far. I was in shock by his behavior. He was extremely aggressive, punching and slapping anyone who came near him, he was throwing things, throwing himself into walls, etc, just completely out of control. I contemplated even taking him to the hospital, but then started doing some research online. I had my mother contact a pharmacist whom we trust, who advised for us to stop the Singulair, as if he was having any side effect, it would more than likely be from that. On Sunday, I started to see some changes in him. Yesterday he was getting back to normal. Today, he's that much better. We actually went back to the pediatrician this morning and I'm actually thinking of filing a formal complaint against the dr. as he basically swore up and down that his side effects weren't from the Singulair. Well as a parent, does anyone really think I'd want to put my child thru this?? It may be different if he had behavioral issues prior to this, but this came completely from left field. I am beyond upset right now, pissed off that this drug can be on the market. How many children have to be affected??? This is very scary to me. My son was only on Singulair 4 days, and I feel guilty and angry that he had to go through even that short period of time on the drug. And then to have a pediatrician basically discount me and say that it has nothing to do with singulair is a complete slap in the face! I won't stop speaking out against this drug and hopefully it will inform other parents of these harmful consequences!!!!