A common insect is the Silverfish, a shiny insect with a fish-like appearance. It is common in the bathroom because it is attracted to humid, moldy environments.
Without a picture or more of an explanation, it's somewhat impossible to answer this question. That being said, my advice to you would be to take a picture and then use google images to find a bug that matches. Look around the corners of the room and you might see where it is coming from.
If they have wings and no stingers, they are termites swarming from your walls. If they do not have wings and have stingers, they are probably ants seeking water. If they do not have wings or stingers, they are probably roaches.
Without a description of the bugs, we will not be able to help you. If you resubmit your question with an accurate description of the bug, we may be able to help you determine exactly what you're dealing with.