1 pill of claritin every 12 hours, when u wake and when u go to sleep.
I think it sounds like allergy or sinus to me. I have the same thing. I started a new job and sneeze, sneeze, sneeze and I went through two boxes of tissues in one day, needless to say - it did not go down too well with other workmates. My workplace is dusty as there are buildings going up nearby. You actually feel like you have the a very bad cold, you are weak and exhausted and ache-ing all over. Maybe when you have a long sleep you are away from the irritant for longer and you feel better. Well good luck. hope you solve it