Should The Contraceptive Pill Be Taken On The First Day Of Periods?

hi! i purchased the althea pills a few weeks ago. i'm supposed to have my period this 23rd. the problem is, i have my period now and i'm here in the office. is it ok if i don't take it on my 1st day and take it on the seconds day instead? i'm currently here in the philippines and it's already 12midnight here. i'll be arriving at home tomorrow at 5am.