You can definitely keep track of your achievements - it's in the main menu, listed under 'Achievements'. They're listed into categories, and if that achievement gives a reward, it will usually have a specific icon beside it (a treasure chest for an item and a medal for a title). It should be noted that all those listed under "Legacy' were achievements that could only be gained in version 1.0 and are now forever unattainable.

Plus at least one seasonal event that has happened since the launch of ARR also gave an achievement and special title that you can't get now (the 'Elite Cascadier' title for completing the summer event 'A Cascadier Reborn' last year).