My memory has been worse than last year, and i am only 23. what causes forgetfulness?

Many things: A person's memory is actually made of different parts and each part has different possible causes for memory loss. In general, memory problems can occur from alcohol abuse, mood disorders, psychosis, stress and anxiety, psychological trauma, head injuries and dementia. However, at your age, you may simply have too much to think about and this may cause problems with "working memory".