HI I have gone through your mail and as you said that you are having flu and cold
for last few days and from last night you have developed gag also with a feeling of dryness in throat.considering your all symptoms I would like to say that you are having upper respiratory tract
infection which is involving part of larynx
also thus giving rise to severe dry cough
leading to gag.You are having feeling of vomiting
that could be due to flu itself.Since you are having this flu/cold like symptoms for last few days and severity of cough is increasing up to gag thus I would like to suggest you to please consult your physician he will do clinical examination and needful investigations for your proper treatment.Thanks.