Hello. Thanks for posting your query here.
I'm sorry about your present condition. The change in your voice, like your voice becoming husky is called hoarseness of voice. It can be due to many reasons. But in your case, as you are a teacher and you are feeling some obstruction in your throat my diagnosis goes more in favour of vocal nodules. Vocal nodules are extra masses on the vocal cords that developed due to mechanical,physical trauma to the vocal cords. These extra masses appear because of vocal abuse or repeated coughing. They are diagnosed by an ENT specialist through some specialised instruments. This is usually seen in singers, teachers, actors, and broadcasters. The prognosis is usually good with proper treatment.
The treatment involves speech or voice therapy and voice rest. I request you to consult an ENT specialist for the case to be diagnosed and to be managed.
Hope this helps.