Hello thanks for asking from HCM for your health related queries I can understand your concern. You are just 21 years old and at this age chances of any organic cause for forgetfulness are very very less. Usually an individual start suffering from memory problems due to organic cause after 60 years of age. If you have no history of seizures, any symptoms suggestive of haemorrhage in brain, any drug abuse, any trauma to brain then in my opinion there is no need to go for MRI or CT scan. Most likely cause of your forgetfulness is underlying stress. Due to stress individuals develop depressive symptoms and they start forgetting the things. Loss of focus is one of important feature of depression and chronic stress. Start taking Vitamin B12 and Omega-3-Fatty Acid supplements and you will see improvement in your symptoms. For persisting stress and depressive symptoms if needed then visit a psychiatrist for evaluation. If the symptoms suggest some depression then take treatment accordingly. Thanks, I hope this helps you. Take care Dr. Seikhoo Bishnoi, Psychiatrist