I did read the book but need help on my Of Mice and Men essay?

There is supposed symbolism in the title ';Of Mice and Men';. I think it is just that Lennie likes mice and he is a man, who doesn't know his own strength and throughout the books, kills mice, puppies, and finally, Curley's wife; but is it more than just Lennie being a man who likes mice?I did read the book but need help on my Of Mice and Men essay?
Actually the title has nothing to do with Lennie and mice. The title comes from a Robert Burns poem To A Mouse On Turning Up Her Nest With A Plough - The best laid schemes o' mice an' men


Gang aft agley, Or to translate this into English The best plans of mice and men often go astray. If there is any symbolism to be suggested here, it would be ';Are you a man or a mouse?'; as Lennie does not stick up for himself.

big hair