New focus symptoms and conditions

My son is off singulair for two weeks now and is showing improvements. He was on it for 7 years and at the beginning we blamed it on steriods, even though his dose was low. When he went off the steroids, the behavior didn't stop. I questioned the allerist if the singulair could be doing it, but was told no, it doesn't have those side effects. I don't blame the doctors because they weren't given the info. He was extremely emotional, cried for no reason, had no confidence, didn't like himself. We on more than one occasion have told his older sister that when he hits his teenage years we would have to watch him for suicide, as his reaction to problems was sooo out of whack! He was on motrin for headaches 4-5 days a week(blamed it on sinusses). Unexplained stomachaches. These symptoms came on over years, not right away. I have always thought that the steroids had done damage because he took them when he was so young. Until the news reports hit, and I started reading other people's stories and doing the "OMG, that's my kid!", I never put the problems on singulair. I was still skeptical, but took him off. His symptoms immediately got 100x's worse for a week. But funny thing is, his headaches are gone, his stomachaches are gone and he seems much less emotional. The strangest thing is, EVERY night, he comes in to kiss us good night 7 or 8 times, and sometimes by the 7th time he is crying and can't explain why. This has been going on for YEARS, EVERYNIGHT, never a break. It stopped! Just stopped cold 7 days ago. Comes in once, says goodnight, leaves and falls asleep. I know this isn't a coincidence. After years of wondering what's wrong with my kid, now I feel like I've been poisoning my him for 7 years. I'm not skeptical anymore.