I've been feeling really nauseaous for the past few days and I haven't been sleeping well because I'm afraid I'm going to vomit.

He prescribed 4mg Zofran twice a day (6 tablets) and 20 tablets of .25mg Xanax and I'm supposed to take one at bedtime.

The Zofran works really well, but I'm concerned about the Xanax though. He prescribed that to relieve my anxiety and help me sleep, but will it work? I'm already keeping everyone awake, and I'm really scared that it's either not gonna work or make everything worse!
What should I know before I take it? I know I can get addicted and I know there are withdrawl symptoms if I take it long enough!