Carrie, I so hear you!! Coco has had the same thing for about 9 days now. I have had it for 4 days and have never felt more tired in my life. coco is on antibiotics for a chest infection, and her nose runniness comes and goes. I tried dimetapp and it did absolutely nothing . I got fess nose drops and use the thing that gets the gunk out, but don't use the drops, just creates more snot!! I use a vapouriser and put eucalyptus oil with it, seems to keep her reasobalby clear at night. The cough is hanging on though and she's waking up so often, it's killing me.
Hope it all clears up for you, would help if the weather improved. IT's been raining and awful all week and Im sure that's why it sticks around. The sun came out for half a day and I took coco out for 10 mins of time in the sun. Im hoping for some more sun in teh next week as Im sure it helps.
good luck and sorry I haven't been much help, but just wanted to let you know we're in teh same position!! xoxo