I have 4 suggestions for a cure.
1. Practice - A lot! The more you practice and rehearse your performance, the more confidence you will have in your yourself. The more practice the less nervous you will be while performing. And therefore you will perform at a "normal" speed.
2. Breathe. Remember to breathe normally throughout your dance. And once and awhile take a deep breathe and let it out slowly - this will give you a pause and your audience will follow you.
3. Add to your performances changes in speed. Make some of them dramatic. Heck, you can even stop for a second or two and add just a little gesture. Add these changes of tempo during all parts of your routine. During the opening, taxseem and drum solo. This will give your performance drama and will keep your audience's attention.
4. Watch some of your favorite dancers perform. Watch their changes of pace. Learn how they add drama to their dance.
I distinctly remember the first time I saw FatChanceBellyDance perform. It was at Rakkasah. I think it was in the late 1990s. Besides their attire being completely different from a Cabaret belly dancer, what really stood out was the speed at which they danced. At least 1/2 of the performance was slow. Slow and very dramatic. Everyone in the auditorium had their eyes glued to them throughout the performance. They are a perfect example of adding change of pace, which results in a dramatic dance.
I hope these suggestions help you in your next big performance!