Izabella
Firstly you are not worthless and please stop thinking you are.
Next, is there any record of the prior approval that you can come back with to prove the project was approved? Nobody should be waiting to a review to turn round and dis-approve something previously approved - these sorts of issues should be raised at the time, not left to fester.
Also to do it in front of another manager was disrespectful to you and you should enter a formal complaint via your HR department about this.
Jackie
www.secretarialsummit.com
Peer Moderator 
