Hello and thanks for posting,

These are not particularly symptoms of cancer, and there is information about dandruff on the NHS Website

You can ask your local pharmacist for shampoo products that will help.

There is also good NHS advice about preventing constipation.

Try and drink 2 to 3 litres of fluid a day, and have daily fresh fruit and vegetables. If you worrying about your bowel pattern, or anxious about your health generally, then do talk this over with your GP. 

I hope this is useful, 

Best wishes,

Vanda