I Think I Have Grass Pollen Cut Grass The Other

I think I have grass pollen cut grass the other day and now have runny nose and drip. Took Mucinex 600 expectorant one tab the other nite. then last nite 2 and was up all nite with very dry mouth. Doc told me to take it two summers ago. Last year did not need it. I took Flunisolide tonite no good, and also old. can I mix and take Mucinex now? I'm 69