Which my heart knows the wide world’s common place? (10)
But if the "plot" isn’t "several," the speaker won’t be too happy about it. Here, he shows his sexual disgust by means of the literary device known as "hyperbole," exaggerating for effect. It really isn’t possible that the speaker’s lady-friend has cheated on him with the entire world, but when you’re as mad as the speaker is, it sure might seem like it.
And to this false plague are they now transferred. (14)
The speaker’s conclusion contains an incredible complex series of multiple meanings centered on the theme of sexual disgust. These meanings are clustered in two words: "false plague." First of all, the word "plague" might be a reference to the STDs the speaker’s lady-friend has picked up through her "false[ness]," or infidelity. At the same time, as we discuss in our "Detailed Summary," Helen Vendler suggests that the word "plague" might be playing off the word’s Latin root meaning of plaga, meaning "wound."
According to Vendler, the image of a "wound" might call to mind… well, the most intimate part of Shakespeare’s mistress’s anatomy. If you put these two ideas together, you get some sense of the sexual insult the speaker is getting at.