At the bottom of the eTicket there is a notation of the reward issued. It is a couple letters and numbers. What does yours say?
It looks something like this:
Code:
Reward Rules:Additional charges may apply for changes in addition to any fare rules listed.
RWD SB7 SF7/NON-END/-TRAN;VALID CO/SQ;NOT VALID AFTER 10/28/2010
All changes must be made prior to the departure date, or the ticket has no value.
The bit in bold/red above is the part that matters.