I was exposed to asbestos for 25 years without knowing it until the company was shut down for 2 weeks by OHSA to clean out exposed asbestos. I am being tested now and would like to know if you have to wait until you're sick and dying to file a lawsuit for unlawfully being exposed.
Although in your circumstance, you should think about consulting with an asbestos lawyer even if the diagnosis comes back negative. It's possible to not show symptoms but still be infected. In that case, you would become sick later on down the road. Seeing that you worked in hazardous conditions for 25 years then you could possibly argue that you are in danger of developing mesothelioma later in your life.
Definitely focus on your medical testing for now though before possibly contacting an attorney. Also, there are mesothelioma support groups and forums online that can give you advice and support. Good luck!