Here’s a tip on how to keep track of old sewing needles: Colour the flat edge of used needles with a marker!
Once a needle is used for a project, mark it. Using a permanent marker, draw a small line across the back of the needle. If it was a small project (i.e t-shirt) then just do a little dash. It probably has another use or two it in. If it was a larger project, like jeans, colour in the entire back of the needle. It’s probably time for a new one.
The type of needle I have available (ballpoint, jeans, etc) is then easy to spot. It also shows how used a needle is. They can also be safetly disposed of once they are used up.
Make sure the coloured side is facing outwards in the case. You can then see at a glance how many needles are used vs new.
I hope you found this helpful! I’d love to know if you have a different way of storing your needles. Or keeping track of used vs new ones.