Had sex with a condom on my fertile week but i took emergency pills 23 hours after,2 weeks later still no period and 2days late. could the ec failed?

Some thoughts...: Plan B (or other EC pill) works very well when taken the day after sex. But, very well is not perfect (and nothing in this world is perfect), so there is a small chance of pregnancy (~zero chance if the condom worked). Plan B can alter one's menstrual bleeding for 1-2 cycles. As always, one should do a urine pregnancy test 3 weeks after taking Plan B, but the condom should have worked by itself.

Very unlikely: but remotely possible. Much more likely is that the progestin in the emergency contraception has altered your usual hormonal balance and delayed your period. Repeated use of emergency contraception is a bad idea. Perhaps you don't feel protected enough with condoms...please pursue more reliable contraception: implant/injection/pills. Best wishes:)