That’s okay.
You should see me completely miss red objects if they are on a green background.
*Insert movie scream queen shriek here*
Cardinals?
Yup, invisible.
Stop signs?
Umm.. *eyes shift* Yup, they look brown to me.
But if I know they are there...
Strangely, I can see red LIGHTS since they emit light rather than reflect it.
So completely missing a clear silica object is well within the realm of “Uhhh.. I did that”.
There are days when I can go to the store with a list in my hand, read it, stare at the item, and miss it, just because my comprehension is at Sublevel 10.
*sigh*
This may not help much, but then again, who knows?
While nothing can be done about red/green colorblindness, there is a technique to use that may be of benefit.
Essentially, it's nothing more than the old red/green 3-D glasses they gave you to watch 3-D movies. What kind of nutcake would walk around outside of the theater with them on?
Um. Here's the point; your left eye will see green things preferentially, because that's the color light it passes, filtering the red. Your right eye will see red things preferentially, and leave green things quite dark.
So on that red stop sign? Your right eye will see the stop sign plainly against a dark background, while your left eye will see a bright background with a dark sign in it. It's this positive/negative disparity that should alert you to the "Ahah! There's something that is called "red" phenomenon".
Just for an experiment, you could try the red/green glasses. If you think it might be worth the trouble, you could have a pair of "driving glasses" made up with a more subtle color difference. You might need help from someone with normal color vision for this stage. You'll want the final product to be more inconspicuous. I think a bright reflective layer on the outside might do the trick. The easy way would be to get some not-too-dark reflective sunglasses and affix a color filter on the inside of the lenses.
I'm assuming that your sister might be able to help you with this. She may be a carrier for the recessive gene, but she likely has normal vision herself. She could be interested for the sake of any future progeny as well.