With patch 2.1, they split servers up into data centers to alleviate congestion. You're asked to pick a data center, not a particular server, the first time you log in after 2.1. After that, it remembers your selection, but you can change to a different data center from the title screen at any time.

Are you sure you picked the data center that contains the server your character is on? According to your forum profile, your character is on Behemoth, which is part of the Primal data center. Check your data center selection at the title screen. Then check the server selection on the character select screen (servers are in the upper right, click to change to a different one).