brendaboo,I agree with the others, tell your Dr. how you are feeling as well as make sure He knows you are seeking therapy and working on learning how to cope with your anxiety.
May I ask how long you have been on Lexapro and what your dose is? If you have been on it awhile your Dr. may choose to increase the Lexapro and stop the Xanax completely as you will be telling him "the 1 mg doesn't even seem to be effective anymore, and at times I have to take One and a half."
Or he could choose to try you on a different benzo
Reading what I wrote, I can see my own "what if?" thinking showing through.
Good luck with the Dr.
Kindly,
Kitt