Our 2.5 yr old beagle mix Daisy snorts, licks her feet, coughs occasionally, has watery eyes, and generally just seems to have allergies. But sometimes, she'll go into a licking frenzy, snort (not reverse sneezing), swallow, and spit up white mucus. During this frenzy she will eat any fuzz or anything else on the floor (something she doesn't normally do). It's almost like she's trying to clear her nose of mucus and swallow it. If I put her in her crate she will lick the floor of it or the sides. If I hold her she'll try and lick/eat my hair or just lick the air. These episodes can go on for hours. We have done the following over the last few months: had chest X-rays,...