Can I negotiate my lawyer's fees after bill has been sent?

If my attorney billed when I think she should not have, can I work with the firm to adjust the billing? For example, my attorney left a voicemail which got cut off, per the objector's attorney, and charged for leaving that message and calling back to leave a second message. Also, she did not clearly outline my options until MANY billable hours later, charging for each question I emailed and her response. I am afraid to contact her for fear it will be considered billable, leaving me in the dark about the status of my case.