Bank of America's (NYSE:BAC) stock is taking a beating this morning, in a startling turnaround from last week's rally that buoyed the share price above $13, where it hovered all weekend. Unfortunately, it looks as if the great news of the bank's settlement with monoline insurer MBIA (NYSE:MBI), which brought an unpleasant legal skirmish to an end, has worn off with the advent of Monday morning.

Bank of America's peers aren't looking too perky, either. Both Wells Fargo (NYSE:WFC) and JPMorgan Chase (NYSE:JPM) are down so far, as is Citigroup (NYSE:C). Of course, JPMorgan has a right to be depressed, as the legal and political problems mount, both for the bank and for CEO Jamie Dimon himself. The others have legal problems bubbling up, too: Wells, along with B of A, is being sued by New York's Attorney General for mortgage settlement abuses, and Citi faces an action over a secretary it provided to William Salomon, of the late-but-not-so-great Salomon Brothers investment firm.

Bank of America, however, is experiencing especially heavy trading activity this morning, which makes me think things could go wrong very quickly for the megabank. So far, less than two hours into the trading week, the big guy has managed to bring its head up above water, just this moment breaking past its opening price of $13.02. Will the plucky bank be able to keep its gains of last week? Possibly so -- but it will likely be a struggle, hopefully one it will be able to win.

Will Bank of America be able to pull the big banks out of the hole they have fallen into? Regardless of the ups and downs these stocks experience today, keep in mind that it is the overall performance of a stock that really counts. As Foolish, long-term investors, we recognize the fact that one-day changes in share price don't make or break an investment. Even stocks have good days and bad days, so it's important to realize that sometimes they're not portents of dire news, but merely squiggles that we can safely ignore.