It's highly recommended to read various translations.
The Lamentations is one of the most beautifully written books in the bible. An inverse of humiliation before exaltation. This book of scripture is instead structured from exaltation of Zion to humiliation and desolation. The writing is stark and includes parallelism, word-links, alphabetical acrostics, and the entire book has both a literal and spiritual interpretation as well as a historical context and an end times or latter days context. The text itself provides the evidence for these things.
"Lamentations consists of five distinct poems, corresponding to its five chapters. The first four are written as acrostics – chapters 1, 2, and 4 each have 22 verses, corresponding to the 22 letters of the Hebrew alphabet, the first lines beginning with the first letter of the alphabet, the second with the second letter, and so on. Chapter 3 has 66 verses, so that each letter begins three lines, and the fifth poem is not acrostic but still has 22 lines.  The purpose or function of this form is unknown. 
Unlike standard alphabetical order, the middle chapters in Lamentations have the letter Pe (the 17th letter) comes before Ayin (the 16th). The first chapter uses standard alphabetical order."
It is clear that at the time Lamentations was written the Law had been found. It has allusions to Isaiah and direct references as well.