Historians and scholars are uncertain as to when Shakespeare composed his sonnets; he may have written them over a period of several years, beginning perhaps in 1592 or 1593. Some of the fourteen-line poems were being circulated in manuscript form among the author's acquaintances as early as 1598, and in 1599 two of them—Sonnets 138 and 144—were published in The Passionate Pilgrim, a collection of verses by several authors. The sonnets as modern readers know them were certainly completed no later than 1609, the year they were published in a quarto by Thomas Thorpe under the title Shake-speares Sonnets. While many scholars have expressed the belief that Thorpe acquired the manuscript on which he based his edition from someone other than the author, modern critics generally see little reason to doubt the text's authenticity. On the other hand, few believe that Shakespeare directly supervised the publication of the manuscript, as the text is riddled with errors—and Thorpe, not Shakespeare, authored the dedication. Regardless, Thorpe's 1609 edition is the basis for all modern texts of the sonnets.
There is a defining complication in the sonnet. “This centers on the ambiguity of the term “mistress” which could refer to a husband’s wife, or, as the Oxford English Dictionary suggests, could also mean “[a] woman loved and courted by a man; a female sweetheart” or “[a]woman other than his wife with whom a man has a long-lasting sexual relationship” (Gregory, 2).
Mira must've felt eager to be able to go on a camping trip along with her parents, by the tone of the first sentence give brief reasoning on why she was feeling eager, it was because it was her first time.