Yes. Postpone 72 is post coital pill and, since u have taken ut on 23, it can protect you from any pregnancy for sex done before 23, or on 23.
Next Steps
wait for the bleeding, usuall after postpone tablets, one bleeds in 7-14 days
if its occurred, you are saved
if no bledding occurs by 14 days after last intercourse, do urine
pregnancy test on early morning sample
Health Tips
if you are going to have such binge sex, best would be to rake ipill after last sex ,asap or within 72 hrs, to get protection from pregnancy. but like all contraceptive, this too can fail, so if person taking postpone 72 like tabs doesnot get menses she must do upt