I been experiencing a smell for the last 6 months or so, sweet smell, there most of the time, my gas smells similar as well, does cancer smell?

May be: It is not established, but it has been reported that dogs can smell some cancers. What you described is not likely to be related to cancer. It may be more of the nature of olfactory hallucination. For good health - Have a diet rich in fresh vegetables, fruits, whole grains, low fat milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex.