up against it

[up against it] {adj. phr.}, {informal} Faced with a greatdifficulty or problem; badly in need.

The Smith family is upagainst it because Mr. Smith cannot find a job.

You will be upagainst it if you don't pass the test. You will probably failarithmetic.

Compare: HARD UP, END OF ONE'S ROPE, BACK TO THE WALL(2).