I get terrible, terrible, morning anxiety lately :( I know how you must feel, it just makes you want to stay in bed and try to sleep for awhile.
The Prozac may not kick in til another few weeks. Everyone is different, you may feel the effects sooner or later. As long as you aren't feeling worse, that's important too that the medication isn't worsening it. I'm grappling with the same issue of taking Xanax every day. I rarely have had to take it over the past couple of years since I've been on my Lexapro which as done a lot for my anxiety and depression. However, my anxiety/panic has flared very badly these past couple of weeks and my doctor is out of town (the most perfect timing!) so I have no choice but to take Xanax when I need it (which has been almost every day, small doses of .25mg or half of .25mg even). My Xanax is prescribed as needed, so I think this is one of the times that is needed!
Give your doctor a call and I'm sure it won't be a problem taking it as needed until you start feeling relief from another medication, even if it is for a bit. As long as you aren't constantly going up on your doses and taking it excessively when it's not needed, I don't see the issue in taking it more frequently with your doctor's supervision.
I know you probably have no appetite from all the anxiety, but try to make yourself eat, even if it's small things. It will help. You don't want your blood sugar dropping, which can add to your anxiety and mood. I've been making myself eat things like oatmeal, bread, all natural snack bars, things that won't be too hard on your stomach. If you have the energy, try to focus on other things like watching a movie, talking to a friend, doing mindless things that will help take some of the focus off your anxiety. I find that to an extent it is helping relieve some of it.