Yesterday, my manager said "you don't have to worry, I'll take care of it"

Today, my manager says "finish it today by any means possible, otherwise I'm gonna get screwed by my boss"

Oh well...

Did you just repeat his words back to him? "you don't have to worry, I'll take care of it"

If this causes you a problem (more than drama), you might have good luck bringing that up as harassment to hr. They tend to listen to hearsay. But only after you boss has given you a verbal warning. Don’t protect your job if it is already protected.

When talking to hr, just use the words, “no means no” a lot. : )

paper trail helps. Note and date what is said.