Hi ZoZo.
Correct me if I am wrong, but just to clarify.
You connected your iPhone to iTunes.
It appears you hit "sync" with nothing actually to be synced?
Have you backed your iPhone up to iTunes in the past, or perhaps just prior to making this mistake?
If not then sadly your information is lost, unless you have backed up via iCloud.
To check when your last back up was completed, simply connect your iPhone and on your information page there will be an option to "restore from backup".
That will list all if any backups and the date / time it was created.
Fingers crossed there is a recent one.
Good luck.
