Low Grade Fever, Pain In The . Brownish Discharge From The Nose. What Is It?

Dear Sir, Last week I had some kind of infection due to which I had low fever and a little pain in nose . I had breathing problem because the nose was clogged. I kept blowing nose to get cleared those excessive mucus . Now I am alright. But today, I have running nose (transparent and light mucus forming excessively). When I got sneeze then a stuff which is hard and very smelly, white and light brown in color and cone shaped come out from the nose-holes inside my mouth. It is really weird and that stuff is a centimeter long and quite thick. Kindly help, I wish to know what it is, how it is formed in my nose. Is it really something I have to worry about it and to see a doctor. Rohit