When can a Non Compete by put in place

I work for a Firm in Virginia and live in Alabama, i have been there 3 years. my Boss recently sent me a Non Competition / Trade secrets Contract. Where i have a issue is when i went there they did 99% Refrigeration Work. I was hired to start and run a new Air Conditioning Department that was nearly 3 years ago. i had to go to the States we plainned to work in and get State Contractors License,by taking each state exam. Becouse the owners Did not have the experence to Qualify with there experence. I have Texas, Louisiana, Arkansas, Tn, Georgia, And South Carolina. they are using the Software i let them use and my License, And told me if i did not sign the Non Compete/ Trade secrets agreement i would be fired!

My issue with that is the agreement they gave me says i cant work in the trade for anyone in any capacity it goes as far to say the capacities.

is there not some law to protect me from this i have a right to work dont i.