What effects does smoking herbal incense have on your body?

Depends on what. "herbal incense" means, since it can be synthetic cannabinoids like k2/spice, or can be synthetic stimulants like "bath salts, " which are combinations of mephedrone and other stimulant chemicals. They have been associated with psychotic breaks, seizures and even death. You don't know what you are getting in these mixtures, and one batch can be different from another.They arent safe. Stop/get help.