I can agree that EI allows a change fee, but the rules are clearly stated at their homepage. You need to call 2 hours before and you did not.
http://www.aerlingus.com/help/help/feesfares/
Whether or whether not Dooleys has provided with you with wrong information is very relevant for you and your case, but irrelevant for Aer Lingus.
You need to direct your claim to Dooleys as they has been booking your trip and should give you the correct information.