The questions that keep me up at night

1. I pump into one container and it tells me I have 2 ounces. I put it into a bottle and now I only have 1.5. How is it possible that every single milk catcher measures differently? Which once is accurate? I'm developing trust issues.

2. If I pour 4 ounces of water into a bottle and then add formula, now the fluid line is at 5 ounces. Am I feeding my child 4 ounces or 5?

3. How is one US fluid ounce a different amount than one UK fluid ounce? Isn't a fluid ounce a fluid ounce?

4. I hate math. And the word "ounce."