I Had Unprotected Sex. Next Day I Started Reading Up

I had unprotected sex. next day i started reading up on STD and started feeling symptoms. So on day 7 and 8 I took 3 pills of 500 mg of amoxicillin I had i took that for 2 days. Then I read that Amoxicillin was not great and that I should take 2 100 mg of Doxycycline for 7 days. so on day 8 I started Doxycycline. On day 9 I went to see a doctor who did a urine sample, the doctor also gave me a shoot of something and a 1 dose of Azithromycin. on day 11 I got results back and they where negative.

Question 1 could the test be wrong because of the anibiotics I had already taken?

after results I was still having on and off pain in testicles and a tender spot in penis urethra tip , so now it is day 18 i have had the shoot and azithromycin at doctors and a 10 day run of Doxycycline.

Question 2 do you think i am clear, even if i still have some slight testicle pain and sometimes urethra at the tip still is sore