Brief Answer:
Please see the answer.

Detailed Answer:
Hi,thank you for posting your query on health care magic.

Looking at your symptoms of Vocal Fatigue(easily tiring of Voice),you might be suffering from Inflammation in the Larynx(Voice Box).The cause might be Allergy,Infection-Viral/Bacterial,Acid reflux,Voice Abuse(Excessive use of voice or use of voice in an abnormal pitch for a long duration of time),Environmental pollutant like Dust,etc.

It would be advisable to consult an Otolaryngologist doctor.He/she will find the cause by doing Laryngeal(Voice box) examination by an endoscope and treat accordingly.

It would also be 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.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 . XXXXXXX 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.

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).Do steam inhalation.
You can take following medicines: Antacid like Rantac if suffering from Acid reflux and Anti-inflammatory like Ibuprofen-if suffering from pain while swallowing.

Hope this answers your question.Take care.

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Brief Answer:
Please see the answer.

Detailed Answer:
Hi,thank you for your follow up query.

Otolaryngologist means an ENT specialist Doctor.
You can search for ENT specialist and Speech therapist online in the place where you are living.

Hope this answers your question.Take care.

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