Sure it is. I do this all the time. You can stay at the airside airport hotel, which, admittedly, isn't cheap. Or get a hotel in the city. For 18 hours, I just stay in the lounge, because I sleep on the planes, and can easily fall asleep in one of the recliners.

You haven't told us anything about your flights, from where to where, for example, or the timings. But, regardless, I doubt that you're going to find lounges with better options than at Doha.