I feel like there is something pushing against my throat. especially with head down. clear my throat often. bad taste in my mouth. any guesses why!?

Reflux: Globus sensation. (feeling of a lump in the throat) can be caused by many things. Acid reflux, irritation from throat clearing , post nasal drip are common causes. Rare causes include masses or tumors. If symptoms continue an otolaryngologist (ENT) should take a quick look to determine the cause.

See your doctor: Problems like these can only be correctly handled by your doctor in person. He/she needs to listen to you, perform an examination and possibly run labs or other tests. That's the only way he/she can find out what's going on and what to do about it.