How to I over come out of mental issues.

I understand your situation. You seem to be suffering from significant health anxiety symptoms related to cancer. You have developed few depressive symptoms too because of the anxiety, including difficulty in concentration, loss of interest and feeling low. Information regarding your sleep, hunger and energy levels too would be more helpful to decide the severity of your condition. Don't worry it is not your fault, it is the hormonal and chemical fluctuations in your brain which is taking a toll on your mental health. It is easily manageable with appropriate treatment, so that dysfunction due to the same can be reduced and your quality of life will improve. Some counselling sessions along with medical help might be useful for you. I would also be more than happy to help you with that if you are looking for online assistance. Discussions will be held confidential. You can directly consult with me through Practo as needed. Online chat consultation is available.