Singulair and athsma symptoms

Im 15 and I never knew that singulair had the side effects that included mental/mood change or worsening depression, etc. Although I did find it strange that I always seemed moody or bi-polar, it never occurred to me that it would be caused by singulair. I've been taking it for about 3 years and before I went from 5mg to 10mg i use to have difficulty sleeping, but just last October when I started taking the 10mg i noticed an even greater change in my moods and mental thoughts, i was always sad, doubtful, mad, and was always thinking of all the negative things in life, in fact I even went through a really deep anxiety stage around the end of October, it was a mixture of the medication and stress i'm guessing, but I couldn't stop crying, I'd cry then forget the reason, start crying again, and wonder what i was crying about or why i was crying for such a thing that lasted for about an hour... Then when I ran out, i sort of just put the thought aside to refill them for the whole month of November and noticed i began to feel more... up-beat, very happy, I cant remember the last time I felt so great for such a long period of time, at least not during my pre-teen through teen years so far. All my friends noticed too, normally i would be complaining about how the day is going so bad, but i can't compare November to any other month during the past almost 3 years, although my asthma symptoms came back. So I started taking them again this Monday, and right away that night when I was doing homework, i was studying about tabacco all these thoughts rushed through my head, I felt bad for the people i loved that smoke, and I started crying, almost blaming myself for their smoking, when i stopped crying i started wondering why i cried... it made no sense, normally i'd just be like, "oh man... why do they waste their time doing that.." and forget about it, but the tired, sad, doubtful feelings came back right away. these past few days I've felt like that, and today before i was about to take my pill i looked at some new information that was never included before about the mental/mood changes, worsening feelings of sadness etc... and it all just hit me like a ball going 90mph.