Yes,
You have got dengue fever.
NS1 antigen is positive only in first 5 days and after 5 days IgM antibody should be tested.
You may read my article on dengue.
"Dengue Fever : Don't Panic, Know How to Deal With It" by Pratyush kumar mishra - https://www.practo.com/healthfeed/dengue-fever-don-t-panic-know-how-to-deal-with-it-29261/post
Next Steps
Feel free to consult directly if you have any queries.