Poor Bank of America (NYSE:BAC). After seeing its share price rise spectacularly in the week prior to its first-quarter earnings report, the stock took a real drubbing immediately after that report was issued. Today, it is getting beat up anew, and I think it is still feeling the consternation of investors about its less-than-sparkly earnings announcement.

Was the report really that bad? Sure, there were weak points, such as mortgage banking malaise, as well as continuing legal hassles in regards to its Countrywide smudge pot of stinky legacy loans. But there were bright spots, too: The streamlining process is working, and B of A has reduced nonperforming assets by $5 billion year over year. Plus, its Bank of America Merrill Lynch division is kicking butt, bringing home the bacon to the tune of $3.68 billion -- a 7% boost from the year-ago quarter's $3.44 billion.

So, why is the share price still falling by mid-morning, having lost 0.68% since the opening bell? Softness in the financial sector as a whole is surely at work here, as the Dow (DJINDICES:^DJI) has been somewhat grumpy itself this Monday morning and now sits 0.12% lower than it did at the open of business today.

Other big banks are feeling unloved, as well. JPMorgan Chase (NYSE:JPM) and Wells Fargo (NYSE:WFC) are also down so far, as is Citigroup (NYSE:C). With their dire predictions about the declining mortgage-writing market, I'm not terribly surprised that the first two banks' stocks are saggy right now. Citi, however, is also down -- by a whopping 0.84% as I write this -- after sailing to a $46.66 close on the day after its excellent earnings announcement, where it beat analysts' estimates right down the line.

One new issue that could adversely affect the biggest of the banks reared its head last week, and might be having a dampening effect on those stocks today. The Brown-Vitter bill threatens to force banks to hold even higher reserves than they do now, never something that banks or their investors like to hear. But that's a future, though looming, threat, and one that may never materialize; meantime, Bank of America and its fellows continue to take a pounding.

By late morning, Bank of America has begun to perk up a little, so perhaps not all is lost. As the big banks face what could be a discouraging day, however, 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. 

Fool contributor Amanda Alix has no position in any stocks mentioned. The Motley Fool recommends Wells Fargo. The Motley Fool owns shares of Bank of America, Citigroup, JPMorgan Chase, and Wells Fargo. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.