Brief Answer:
Do an uroculture.

Detailed Answer:
Hello dear, welcome to Ask a doctor's service.
I read your query and here is my advice.
I don't know which kind of antibiotic you are using about the bladder infection.

I think the antibiotic you are using is not working because you don't feel any better after three days.
This means that you are having resistant infection.
The best thing to do is to do an uroculture which will show which antibiotic can be used best for you.
If possibly visit your doctor again.
Meanwhile take acetaminophen or ibuprofen for fever and chills. Have lots of fluids especially cranberry juice to help flush the bacteria out.

Hope I have answered the question.
Let me know if I can assist you further.

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