I think you are probably thinking about the 16gb internal memory which is listed as a sd card on file explorers. most networks are not genorous with memory, and the odd ones that ship with a sd card tend to be 2gb not 16bg, and even then it would not be in the phone ready, it would be in the box in it's own container so if you got a sd card with it you would have had to out it in yourself, something i'm sure you would remember doing. also, it is not exactly easy for a sd card to drop out the s2 because of port location. I would say as before you have mixed this up with 16gb internal memory.