It's quite important to report any injuries that you get on the job as soon as you can. If you fail to do this, your company may fight with you over whether or not they have to pay compensation. The company's executives may claim that you hid the injury, and they will deny the payments.
For example, there was a case in which a man suffered a minor injury when he was struck while at work. It didn't seem very bad the first day, so he said nothing. It slowly turned into a bruise, then a welt and then an open sore that had to be treated by a specialist. This was two months after the incident, and the company said he didn't report if fast enough.
The problem is that a small injury can become major if it gets infected or if there are other complications. It may have cost the company a small amount to treat right at the beginning, but by waiting so long, it may cost far more. The company won't want to pay 10 times what it would have cost in the first week if the employee should have said something initially.
Of course, it can be hard for employees to know what to do when they are barely hurt. Should every single scratch or bump be reported? Many people will tough it out, not trying to hide the injury, but getting into a bad situation when the company accuses them of doing just that.
If you're hurt, it's always best to report it as soon as you can, as this strengthens your position for compensation in Maryland.