I had 4 ct of the brain due to headache all my ct where normal. what risk did i cause myself getting all those? they were done n 2012 im very scared

None: If a patient needs to have 4 head CT scans because of medically worrisome headaches, that is fine to do. There is no harm in doing a few head CT's as along as the scans are needed for medical reasons (because life is about balancing risks and benefits). The patient should keep working closely with her primary care and neurology doctors so that future scans will be done only when very necessary.