Brief Answer:
Not serious but you need treatment,consult doctor

Detailed Answer:
Hi XXXX,

Thanks for writing to us.

I appreciate your decision to quit smoking. It is really a good step for your healthy future.

You seem to be suffering from smoking withdrawal and also may be some sore throat/pharyngitis.

Withdrawal symptoms includes headache, nausea, not feeling well, anxiety, restlessness,gastric discomfort,constipation etc.Normally withdrawal peaks around 3rd day and then gradually decreases. Completely stopping of withdrawal symptoms can occur from one week to 6 months depending upon quantity and duration of smoking as well as treatment of withdrawal taken or not.

In your case I think it will not last for more than one month if you do not take treatment. But you should go to psychiatrist/deaddiction specialist for the treatment otherwise symptoms may increase your craving and you may restart smoking to curtail the symptoms.You are young fellow and I think you should be helped and made free of this habit by professional help.

After examination doctor can give you medicines like propranolol,bupropion and short acting benzodiazepines depending upon withdrawal. As well as deaddiction counselling can be done there.These medicines can be stopped according to doctor's advice.

Sore throat is not the withdrawal symptom but you should be examined physically to check that there is pharyngitis or not or it is only just a part of anxiety.And depending upon diagnosis you can be treated for the same.

Breathe heavy (with mild chest pain for 1-2 mins) after long walk is likely withdrawal anxiety symptom considering your age.
But yet physical check up to be done by doctor for confirmation.

Hope I have answered your query, I will be happy to help further.
regards,
Dr.Chintan Solanki.

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