will i be charged fees if auto payment isn't taken by the deadline?

when i filed my taxes i chose direct debit to pay what i owed, and set the date for april 15, which happens to be the deadline (but it's also the day i get paid which is why i chose that date). it says that it may take up to 5 days for the irs to take the money, and i've seen some people say it takes a week or two. just making sure - i won't be charged any penalties if they take the money after the deadline, right? since at that point it's on them? please advise - it's my first time using this service.