I was diagnosed with an upper respiratory infection, was prescribed benzentate 200mg (3x daily) & prednisone 20mg and 7 days later, i feel 100x worse?

See a doctor: Sometimes, an initial (viral) infection can set the stage for a worse, secondary infection. This second round could be caused by a bacteria, since you've already been weakened by the first round. Kind of like a tag-team of germs - so for that reason I think you need urgent evaluation. I would go to an Urgent care center or call your doctor now.