Throat is sore and feels swollen have an awful metallic taste and weird film sensation in my mouth constantly what could this be? The mucus is awful

Could be. Virus, bacteria infection, fungal infection, gum disease, GERD, Sinus infection, etc. Please see BOTH your General Physician and your General Dentist. You may have coincidental but unrelated problems, and therefore need both examinations.
Many possibilities. This could be a fungal or other tongue infection, dental or gum disease, post-nasal discharge, acid reflux. Go and have an ENT doctor or a dentist examine you and go from there.