It is no problem assuming you are eligible for immigration entry.
You should be able to have your luggage checked through, you will either need to take your hand luggage with you or find a left luggage store.
There is a T3 Baggage office which is at the far end of arrivals near the taxi queues/DNRD office that will let you store baggage.
I do this quite often - 15 hour layovers are no problem at all.