If you are applying for short-term disability benefits, you may have run up against something called the elimination period. This is a period of time that can range anywhere from a few days to over a month, during which you have to prove that your illness or injury really is preventing you from continuing to work. Sometimes injuries do not require an elimination period, but illnesses do because illnesses could always clear up. That means you're faced with several days without pay. Covering those days isn't impossible, though, and you do have options that will provide you with money during that time.
Sick and Vacation Days
Using up vacation and sick days to cover the elimination period is the easiest way to stay financially supported, even if the injury or illness was not a result of work. In fact, many companies will require you to use up your time before you can receive disability pay. It can be disappointing to lose so much time that's been built up, but using those days will allow you to still survive without causing you too much financial stress.
Retirement Plan Hardship Withdrawals
While you could always take out a loan against one of your retirement plans, those loans have to be repaid, often with interest. Trying to make those up can be difficult. But many retirement plans do allow for no-repayment withdrawals if you're going through a hardship. The circumstances that would qualify as a hardship vary from company to company and from plan to plan. But if you really need money now, call the plan administrators and ask them if your retirement account has the hardship-withdrawal option.
This option may not help if you're already applying for short-term disability, but once you're back to your normal activities and schedule, you can apply for secondary insurance that can cover you if you find yourself applying for short-term disability again. Look for policies specifically designed to cover lost pay during times when you're sick or injured. You likely would not be able to get a policy now because you're already dealing with a problem (that would be like trying to apply for primary health insurance after you've gotten sick). But you could certainly call companies and ask them about application processes so that you're not caught unawares if you find yourself back in this situation.
If you find yourself having trouble applying for benefits, or if you have other problems with the elimination period, talk to a disability lawyer. Short-term disability should be easier to deal with than permanent disability, so a lawyer should be able to help clear up any situations that arise.