If multiple pairs of earphones show the same result, then it sounds like the audio jack(the hole you plug your headphones into) in your computer is faulty. These break down all the time because they are under a lot of physical stress. If you take the laptop to a local computer repair shop they might be able to repair it for you on the cheap, extending the lifetime of your laptop.
Do the speakers work properly? If the speakers don't work right, then you may have a bigger problem.
Have you tried USB headphones? They might work even if the audio jack is broken.