We do not see the interaction between the Nurse and Juliet when the Nurse returns from visiting Romeo at Friar Lawrence's cell, after the Prince has banished him from Verona. Therefore, I assume that you are asking about the interaction between the Nurse and Juliet after the Nurse returns from asking Romeo's intentions toward Juliet. In this moment, the Nurse complains about how much her errand wore her out. She says,

I am aweary. Give me leave awhile.
Fie, how my bones ache! What a jaunt have I! (2.5.26-27)

Juliet is in a big rush to hear what news the Nurse brings, and the Nurse either gets a little irritated by Juliet's lack of concern for her or she is merely teasing her young charge because she knows how anxious Juliet is to hear about Romeo (one could interpret it either way, I think). The more Juliet pesters her, the more she complains about "how [her] head aches" or "[her] back, [her] back!" She finally blames Juliet for "sending [her] about / To catch [her] death with jaunting up and down" (2.5.54-55). Finally, when Juliet speaks sweetly and flatteringly to the Nurse does the Nurse eventually give in and tell her that Romeo wants to marry her today.

The Nurse is hot and winded from her walk back to the house and wishes to rest a bit. Juilet is very impatient (as are all 13 year old girls!) and wants the Nurse to tell her everything immediately. She begins to bombard the Nurse with question after question without pausing to wait for an answer. The Nurse is trying to catch her breath and tells Juliet to give her a second. Also, she then seems to tease Juliet a bit by taking her time telling her what Romeo said. Perhaps it's because Juliet was so impatient that the Nurse decided to prolong her response. However, the Nurse eventually asks Juliet is she is free to go to confession (shrift) that afternoon because Romeo will be waiting at the church to marry her.