I rubbed/itched my ear the other day and immediately developed muffled hearing. my hearing has been very muffled for 3 or 4 days now. is this serious, or can this go away on its own? could over-the-counter ear drops help?

Wax in ear: You need someone to look in there and prob clear wax out.

Rule out ear wax: "Common things commonly occur" & most common cause of sudden onset muffled hearin is ear wax. You might be able to check it out using mirrors or have relative or friend check it out. Inexpensive ear drops available at all pharmacies may well be worth a try. Consult with with otolaryngologist Dr. if ear canals are wax free because "Uncommon things are common in the people in whom they occur".

Ear wax: You may put some baby oil in the ear to soften the wax and it may come out on its own. You may try an over the counter kit to wash out ear wax. It is not a good idea to use ear swabs. Have a healthy diet, exercise 30 minutes/day, drink plenty of water daily so your urine is mostly colorless, have safe sex, no tobacco alcohol weed or street drugs. For nutrition: http://www.choosemyplate.gov/.