If I had 1 beer on Saturday, and may have a alcohol test on Tuesday, will this show up on a alcohol test? I am a female weighing 128 lbs.

If you are having an ETG test it could be positive. Alcohol can be detected in that test for a long period. If it is just a regular alcohol in urine test it will NOT show up.

And of course the test is the least of the worries, most people are caught by someone turning them in, someone you drank with, ex who gets mad and turns you in, or many by posting their photos of thierself drinking on Facebook