If you used a condom you had no risk at all and had no reason test. Good for you for using a condom to protect yourself. So lastly, you didn't have a risk and you can forget about this and move on.
actually i did sex on 30dec and i used condom and i am 100% sure i condom was not leaked and broken. i started drunk and smoke 23dec and stop 31st dec. on 31st Dec i took alot drink and smoke alot next day 11jan on morning i starterd bad cough after few days i got soar throats. i went to doc and i shared to doc whatever i did. doctor firstly did my normal blood test everything was fine after 15days but stil that time i had soar throats and dry cough. But i didnt have other symptoms like runny nose, flu, cold my temperature was not more then 36.6 i checked regular 15 days. but after read symptoms on google i m feeling pain in my hands elbow sometimes in knee and i dnt have any lymph nodes doctor check but i m always feeling that. in my reports my hemoglobin was 17 doctor said dont wrry just donate the blood. i am not feeling hungry and have too much tention and cause of tention unable to sleep
And no, antibiotics would not affect the test result.
If the test was a 4th generation combo/duo test than your 28 day test is conclusive. This has been stated by many experts.
May i ask what your risk was?