B,
So sorry you are going through this

I know AMH can drop pretty quickly when we hit 40 (which totally sucks) but you also have to remember it is only a guide to success. On paper I have great AMH levels (17.something). Well I did 12 months ago!! But I still don't have a baby. On the other hand, women with a lower AMH have gotten pregnant. You know what? I sometimes think it comes down to dumb luck...
Get tested again for your own piece of mind. But in the meantime remember it doesn't come down to a test.

Stay strong x