Are your thoughts repetitive & intrusive? Are these thoughts creating any distress? if they do, we can diagnose this condition as OCD.
To know more you can read about the causes of depression here.

To manage insomnia you need to maintain a consistent sleep schedule, create a sleep friendly environment, follow a relaxing bedtime routine, avoid stimulants. Its also imp to engage in regular exercises and practice stress management like breathing exercises.. Visit a psychiatrist or a sleep specialist to cure the problem. 

Read about this for more information - FDA Approved New Treatment for Insomnia

If you're struggling with forgetfulness and shyness, there are some general strategies you can try. To improve memory, break information into smaller chunks, use visual aids, and establish routines. Overcoming shyness involves starting with small steps, practicing self-acceptance, seeking support, gradual exposure to social situations. You may consult a psychologist or a therapist as well for overcoming social anxiety and improving self-confidence