I have been getting dull head pains everyday on one side or spot on my head. What may this be? Brain tumor? Aneurysm?

Many causes for head. There are many causes for Headaches. One sided headaches are often caused by migraine which is more common in people who have excessive stress in their life. So you need to find a headache medicine that relieves your headache, slow down at work and exercise regularly(like a daily walk). A visit to a neurologist may be helpful if the headaches get any worse, so that further testing can be done .