When i breathe I can feel my ear drum pulsing?
There is a “tube” connecting your middle ear cavity with your nasal cavity. It is called the Eustachian tube (or auditory tube or pharyngotympanic tube) and serves the purpose of regulating pressure and draining mucus from the middle ear. The Eustachian tube is normally closed but opens to let small amounts of air through to equalize the pressure between the ear and the outside air. It sounds like you may have a patulous Eustachian tube (or patent Eustachian tube). It is a rare condition, where the Eustachian remains intermittently open. With it open it causes a sort of echoing sound of your breathing, heartbeat and speech. It can temporarily go away when your head is upside down. I would go see an otolaryngologist (ear, nose, and throat doctor) to talk about treatments and what may have caused this. Good luck and Feel Better.