Marijuana causes anxiety!?

Ok, well, my dad has gotten into some trouble (nothing that bad) with the law before, he says it's because marijuana and cocaine he used in his teen years, and now he has stress anxiety, and his doc says it might be passed down to me. But the thing is I LOVE SMOKING, it literally gives me a reason to live my life again! Plus I just use Mary J and it's only maybe once or twice a month. As opposed to the MASSIVE amounts of drugs HE took once a DAY. Not only do I enjoy it, I use Mary Jane for my headaches, and the stress physically on my body. So if I stop, my pain physically will occur again! Then, I can't function correctly. Medication doesn't work on my body very well that's why. Ideas?