Home alone for a week?

Here's the deal, i was ment to be going to Australia with my friend and her parents for 2 weeks next month, but due to unexpected circumstances, i doesnt appear that it will happen. My parents had arranged to go to another town, about 2 hours away, for the second week in which i would be returning, and we had both planned to return on the same day. the house that my parents are staying in is only big enough for 4, which was planned to be my parents, brother and his friend. I havent told my parents yet that the holiday has probably been cancelled, but i;d like to stay home alone that week. i'll have just done exams and i'd need the peace and tranquility.... I know that if they did let me, they'd leave PLENTY of money, LoADS of food and i'd have plenty of credit in my phone. I wont bring anyone back to the house, i'd feed the fish and walk the dogs... I'm really mature for my age (16) and i have aunties and cousins living pretty close. Is it ok? (ireland)