Estelle,
I am with you, if I could carry the sample to the lab and push the tech out of the way, to use the equipment I would.
Don't worry about being negative. When I am feeling down, I come here to peruse other people positive success.
Sometimes writing a commiseration to someone you don't know who is going thru something similar is quite healing in and of itself.
Sometimes writing a post where you actually help or provide encouragement to someone is even better.
You know how those posts affect you correct? Pass it on