Bad customer or bad me?Did I do something wrong ??

[Rosalie x]

No, you did nothing wrong.
But it was a mistake giving into him because he sounded 'really sweet', as he was obviously just doing that so you would give him more than he paid for.
As you learned, he was not sweet at all.
In the future, don't let anybody try to barter with you and maybe write on your profile that the 15 minute session is for what you provide only and not the 'full experience' 
xx  There are plenty more actual nice guys out there, who wouldn't barter with you in the first place because they know better. Anyone that tries to barter on prices set by me will just get a message saying I don't see barterers and that's it! 
He's been a timewaster, so do the comments thing in messages and report him to adultwork as a timewaster and explain what happened.
Also be aware, he may try to create another profile and message you. Someone did this to me. Check the AKA and then report them again to adultwork.
Hopefully you don't come across another unpleasant person like this!