I've been having particularly bad allergies lately. I've been referred to Zyrtec by a couple of people; when I went to the store I actually bought Zyrtec D because I've had some success with Claratin D before, whereas regular claratin seemed ineffective. It's been about an hour or so, and while my eyes are no longer itching I'm just as congested as before--something that this product is supposed to allieve. Is it typical to see certain symptoms treated, but not others? Or is this product just not the right one for me?