Thank you for asking your query at DoctorSpring.
Since you had a 'safe' encounter ( I presume condoms ) the symptoms is not suggestive of any STD. In fact a STD is more likely to present as a discharge or genital lesions than a 'fever and sickness'. This is more suggestive of a viral infection. (non STD related viral infection - just like Flu). Anyway its good that you have gone for STD tests. If they are negative you can be sure that you are safe.
Hope this helps
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