The phrase we use is "to drop a bombshell (on someone)". It means to give them news that affects them and shocks them. The news is usually negative, but it can be positive. You wouldn't use "bombshell" to mean "breaking news". From Google News: "A senior councillor has dropped a council tax bombshell on Cardiff householders, warning rates could rise by 5% a year for the next three years..."

I used to be a blonde bombshell.

Sara you need to consult a dictionary, write your own sentences, and we.shall correct them for you. You will not learn if you just give us instructions to do this and that.