Vaccination dose query. On all points!

My son is 51 days old and on 45th day I went to one govt dispensary for first vaccination but only Pentavalent was available so they asked to come after 2-3 days.. so today I went to one bigger government hospital but again same thing that only one vaccination was available.. so they said that vaccine might be available after 3 days so come again or take only one penta-1 vaccine now and other ipv and pcv you can take on next month vaccine.. we have not taken any vaccine as wanted to check after 3 day and all can be taken in one time and if not then I will take only penta-1 and rest later.. So is it fine to take vaccine in a gap.. I am already late by 7 days so is it ok for delay by some days.. someone said that penta-1 is manadatory to be taken on priority and rest when available. Please suggest on all points