Brief Answer:
anxiety disorder with cannabis use, need to consult a psychiatrist

Detailed Answer:
welcome to HCM
As I can understand here the main target issues are
your apprehension regarding having or development of lung cancer.
Con current anxiety and cannabis use problem.

Regarding the First concern, Its is important for you to understand the possible presenting symptoms of lung cancer. These could be such as Blood in while coughing, Significant weight loss, loss of appetite, general feeling of being ill, fatigue and loss of energy. If there present such complaints, one would need to undergo certain investigations to diagnose and confirm the cancer. Above all this, one need to understand that 90 % cancer conditions are benign and can be cured.
My suggestion to you will be to
consider quitting smoking.
consult a local chest expert for an opinion. Depending on which investigations can be indicated.

The other important issue to address is of anxiety and cannabis use. It is highly suggestible to quit smoking cannabis as is not only predispose to smoking related complications but also predispose an individual for psychotic conditions of such as schizophrenia, hallucinations, paranoia, etc.
Regarding anxiety, i suspect that it is secondary to your apprehension about lung cancer. In such case settling your apprehension can subsequently resolve the anxiety issue. Other possibility is of an independent anxiety condition, in case of which there is need to evaluate a detail history and pattern of it.
My suggestion for you are
Consulting a local psychiatrist is best advisable here as there are multiple problems of cannabis use and anxiety to address.
Anxiety disorder, panic episodes with co morbid cannabis use is highly suspected.

Meanwhile i suggest ti continue drug clonipin as advised. tab cetrizine 5 mg( anti allergic) twice a day can be taken for 3 days for cough due throat irritation.
Hope you find my suggestion help full.
for further queries kindly revert back here.

Regards,
Dr Pankaj

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