Don't get too upset – nearly everyone messed up. In fact, a 2012 survey by the nonprofit Consumer Federation of America found that two-thirds of middle class Americans said they had made at least one "really bad financial decision" in the past. And that's just the people who are admitting it.
The good news is that it's not too hard to get back on track. Here's what you need to do now to correct last year's financial mistakes – and avoid making them again next year.
Worst budgeting mistake: Not having an emergency fund
About 75 percent of Americans don't have enough emergency savings, according to a 2013 bankrate.com survey of 1,004 adults. Americans tend to have a lot of "good" excuses for not having an emergency fund. Maybe you are trying to aggressively pay down debt, think you don't earn enough or just want to use your disposable income to have fun. These are all worthwhile reason, but you know what else is worthwhile? Not going deep (or deeper) into debt if something catastrophic happens.
As soon as possible, create an emergency fund of at least $1,000 – that's enough to cover most emergencies. Then, try to adjust your budget to a point where you're saving 20 percent of your income every month. You don't need to put all 20 percent in your emergency fund; you could also save for a big expense like a car or house down payment. The important thing is to make saving a regular habit.
Worst investing mistake: Not taking advantage of your job's 401(k) match
When you don't take advantage of your job's 401(k) match program, you are throwing away money. Most employers who offer a 401(k) plan will match your retirement savings contribution. If you haven't already enrolled in your company's 401(k), do so as soon as possible. Not only will you get that sweet employer match, but the sooner you start saving and investing, the more that money will be worth when you're ready to retire, thanks to compound interest.
Worst lifestyle mistake: Not cooking for yourself
A lot of people don't know how to cook. That's a shame because cooking for yourself instead of dining out can save you thousands of dollars a year (not to mention help you eat healthier). Let's take breakfast as an example. For $2.99 you could buy one serving of hot oatmeal at Starbucks, or you could go to the grocery store and pay the same amount for 30 servings of oats.
Don't get intimidated if you've never cooked before – just start small. Even making a sandwich at home can save you money. If you have a friend who is a good cook, ask him if he can show you a few techniques. And remember, if you make something that tastes bad, that's just part of the learning process.
Worst shopping mistake: Buying new versions of things you could fix
Too often, we replace things entirely when it would be much less expensive to just fix them. According to a survey by Harris Interactive of 2,000 adults this year, 64 percent of Americans believe it's financially smarter to replace an entire computer that runs slowly instead of upgrading parts on their own. Yet you can easily speed up your old computer by optimizing your hard disk, installing more RAM or removing spyware.
Before you replace something, always look into your repair options – even a quick Internet search can be helpful. There are so many other things we can fix – shoes can be resoled, furniture can be refinished, kitchen knives can be sharpened – the list goes on and on.
Worst career mistake: Not asking for what you want
We don't like asking for things we want at work. It gets even more difficult when the job market is tough – you might not want to make waves at your place of employment by asking for a raise. But that could also mean that you sit around feeling sorry for yourself, asking questions like, "Why can't my boss see that I'm bored? Why can't I make more money?"
Instead of waiting for things to go your way, decide what you want from work, gather your evidence and state your case to your boss. You might not be able to get a promotion right now, but maybe your boss could expand your duties so your day-to-day work is more satisfying, and you'll be better positioned to get that promotion when a position becomes available. The raise might not happen immediately, but you'll get a chance to show your boss how hard you're working and how valuable you are to the company.
Meg Favreau is the senior editor for the personal finance blog Wise Bread, which covers rewards credit card mistakes and other personal finance tips.