No, advent isn’t the same all way through. It begins with thoughts of the end of the world and the last coming and ends up all excited about Christmas. Liturgically, it can be divided into two parts, for example there is Morning and Evening prayer for ‘Advent until 16th December’, before having different sets for specific days. Part II covers the last octave of Advent, and is the ‘excited’ part. We also save specific hymns for this part of advent, most notably the O antiphons (O come, O come, Emmanuel, and the like).