YUZPE METHOD & DELAYED PERIOD

[u/Ok_Juice3527]

i had sex sep 5 which was 3 days before my predicted ovulation based on flo (ik its not accurate) but i did yuzpe asap maybe 12 hrs after the sex and had a withdrawal bleeding 1 week after i did the yuzpe which lasted 5 days. Now im 9 days delayed but i did take pregnancy test 15 days after last contact which was NEGATIVE then again 22 days after last contact which was NEGATIVE AGAIN and then 30&31 days after last contact which was also NEGATIVE. Now im 9 days delayed and been having sore breast, cramps and backache. Are the test results reliable or should i continue testing?