If the rosy was able to get it down and keep it there without regurgitating, then the meal was most-likely a suitable size. Although I haven't seen your snake, I would think a 2-footer would be able to eat a fuzzy rat no problem. It is only when the snake has much difficulty getting a very large prey item down that I would worry. Give your snake a nice warm (85-88 degrees F) basking spot to help him digest. Don't handle it for about 5-7 days, or until the lump goes down. Good luck!