Answer:
My first half means container. Not a lot of people understand my language.
As I went over London Bridge I met my sister Jenny; I broke her neck and drank her blood and left her standing empty.
When I point up itβs bright. When I point down itβs dark.
What gets bigger the more you take away?
I am black when you buy me red when you use me when I turn white you know itβs time to throw me away.
Lovely and round, I shine with pale light. Grown in the darkness, a lady's delight. What am I?