And that is why you shouldn't google. Technically, any pain or dysfunction you have in your body could be linked to CA. Effusions of the middle ear can be very persistent, and often take a nasal steroid (yes nasal) and a decongestant and still might several weeks to clear up. If it continues to persist see an ENT. There are several missing links in your story I don't quite understand. First why an ear drop? Did you have both a middle and an otitis externa (canal infection)? Also did you have drainage? If so, did you follow up with your doc? It even possible an infection perforated your ear drum. Now before you panic those heal but could produce a muffled hearing issue for quite awhile.