I have found in one book a intersting sentence. The situation is about that a couple is having a quarel because the guy cheated on his girlfriend.
After a while, the guy says:

"By now, I am really bricking myself. My girfriend nas no idea what Pablo might do to us if he finds us here."

How to understand "bricking". As much as I have understood the guy is defending his position, proecting his view of the situation and so on.
It that correct ?

thanx a lots in advance