All the RCCL ships have wheels with both a 0 and 00. That's 38 in all. Your $5 bet covers four numbers. Your odds of winning are 4 in 38 or once every 9 1/2 spins.
Your 9 1/2 spins will cost you $47.50. Your payout will be 8 to 1 or $40. In other words, on average, you will lose $7.50 for every 9 1/2 spins.
You should be very happy that you have been lucky and, as you say, you had a lot of fun. Just consider gambling to be entertainment, not an investment.