There is no such thing as a 'normal' memory. Everyone is different. Most people occasionally forget what they went into a room for, or can't quite find the word that's on the tip of their tongue. When this happens, we usually remember later on what it was we were looking for, or the word we were trying to say.
If you find your memory getting worse, it can be worrying. Many people think memory problems are a normal part of old age, but sometimes, especially if it is affecting your ability to cope at home or in company, they can be a sign of a medical condition. Often there are ways of helping and learning more about this, so it is important to see your GP.
If you are concerned, take a look at the "Worried about your memory?" booklet.