You know that a) you've worked in a lab too long and b) you have an overly acute sense of smell when...

you can tell the difference between bacteria growing in lag phase and in log phase by how the culture smells.

You know you've worked in a lab too long when...

You find yourself looking at the antibiotics tube thoughtfully, thinking, "Wow, we've got needles in the lab. I could just inject this stuff and skip going to the doctor entirely."