I have been taking Singulair for almost three weeks now. I have ...

I have been taking Singulair for almost three weeks now. I have had problems with ear infections/inflammation since May of this year. I have a new Doctor and since I also have seasonal allergies he recommended Singulair. I was wondering why no other Doctor including the allergist that I see ever recommended Singulair to me. At first I thought it was a great idea, but I have noticed the headaches are getting worse, and I still wake up with a very dry mouth. I'm not sure it's worth taking anymore. I was thinking that perhaps the problems I had were also a result of the antiobiotics I was taking, but I finished that prescription a week and a half ago. So it can't be the antibiotics causing the trouble. The only other medication I am taking is the Singulair. Thanks.