Edits do not save to correct project

Look I'm not sure how this happened but here's the run down.

I have two projects open at once, one contains a list of all my mainly used assets (A), whilst the other is the main project (B) - example, short film.

I was just editing today and noticed that whenever I would import anything into B like specific footage, it would also import to project A... I would like to emphasise I am editing on a sequence saved in project B. Anyway so I think it's odd that anything I import into B ends up in A's media library, so I close project A (no save prompt given) to see if a restart would fix it.

Closing project A (just project A), closed project B with no save prompt, losing all my progress, even progress I had previously saved?

Not sure how to replicate, but just letting team be aware