There isn't sufficient information to suggest a specific diagnosis. As you have chills, I would advise you to visit a MD general medicine so that you can be examined and undergo examinations such as CBC, peripheral smear, Dengue IgM, etc. to find the underlying cause of the problem and have it treated accordingly. This is a public forum so medicines cannot be prescribed on this medium.
Next Steps
Follow the steps as advised
Health Tips
If condition persists or worsens visit the ER at the earliest