Sensitivity issues symptoms and conditions

I have been on Doxy since the 29th for possible pneumonia/sinus infection-deep cough,swollen nodes sick for almost three weeks.
I am pretty healthy at 39 but got this whopper that wouldn't let go.
The doc prescribed this Dox 100mg,along with Prednisone. My cough is clearing up,feel better overall, but have had very vivid, chaotic, and scattered dreams.
A little GERD (I have Barretts Esophagous so wouldn't feel too much hburn) today, but the main issue was the pill, so strong I projectile vommitted three times yesterday, have had major runs, and dry skin.
It works best for me after food and loads of water/vitamin water, and staying very hydrated. I drink a lemon ginger tea to soothe my stomach.
Other than that I am in Arizona and haven't had any sun-sensitivity issues.
I have had a headache as well for two days, but the vomitting could have brought that on, I almost popped a gasket it was so sudden.
Well, it seems this one is a doozy, get all of the facts on it-especially the NO DAIRY when taking it...
Hope all readers feel better!