I'm 24 year old male. From almost 10 days i'm facing very light dry cough with little nose blocking in the nights. Four days ago, throat pain was there with yellowish and solid phlegm. After taking medicines, I got rid off that. But from 2 days, dry cough again started with little stuff in nose which is not at all hindering my breathing. I work at construction sites. What to do to get rid of this and what might be the reason. Is it any allergy? Thank you in advance.