Hi,thank you for posting your query on health care magic.
Looking at your symptoms,it seems you are suffering from Laryngitis(inflammation of voice box)
You may find relief by taking
Analgesic and Anti-inflammatory like
Ibuprofen along with Antacid(like Rantac) and a Cough Expectorant like Containing Ambroxol/
Guaifenesin.
It is advisable to consult a Speech therapist.He/She may guide you with few techniques and exercises for correct way of production of voice.It is much needed as you are a singer and teacher.You must know how to produce voice in a correct way.Otherwise ,improper way of voice production may lead to injury to your
vocal folds.
Most of these exercises begin by eliciting the correct voice production technique using the most facilitating sounds and combinations of sounds.Some of these techniques are as follow:
Accent Method: This program uses rhythmic exercises to facilitate the coordination of vocal fold
vibration with appropriate air pressure and air flow.
Confidential Voice: Confidential voice is designed as a temporary style of voice production used to help facilitate mucosal repair.
Digital Laryngeal Manipulation: Also called laryngeal
massage, the focus of this technique is to decrease excessive contraction of the muscles of the
larynx .
Lee Silverman Voice Treatment (LSVT)-emphasizing both the production and the habituation of loud voice.
Resonant Voice:Resonant voice techniques aim to increase the power and clarity of the voice while decreasing the vibratory forces that can contribute to mucosal trauma.
Vocal Function Exercises: This approach is a three-component program of warm up, pitch glides (high to low and low to high) and sustained vowel phonation at selected pitches.
It is also advisable to consult an Otolaryngologist doctor.He/she will find the cause of hoarse voice and mucus collection in throat by doing Laryngeal(Voice box) examination by an endoscope and treat accordingly.
Till then,give voice rest.Don't shout or whisper.Speak only if it is necessary in a soft voice.Avoid cold,spicy,oily food.Avoid dust,smoke and other pollutants.Drink lots of fluids(warm).
Hope this answers your question.Take care.