Sounds a bit funky to me too. The commission on short sale should be at least 5%. Sometimes the lender will lower it if same agent represents both sides but all she needed to do was to have a colleague represent you to ensure full commission paid. Then she could throw the colleague a small bone for their time and each aprty would have separate representation which is better any way.
I think you should probably have that talk with your agent. I wouldnt be accusitory but I would want to know what happened. There could be a perfectly good reason. For her sake there better be…