Whats the side effect of incense?

Smoking an incense is not smart. when i was on probation they told me there was a "legal marijuana" and it turned out to be an incense. People say you cant die from this but YOU CAN. i smoked it and almost died my heart stopped and everything and ever sense then i get what the doctors think are anxiety attacks but i never had an issue with anxiety before i smoked it!! i can honestly say it was the scariest thing ive ever been through. Please do not try it, yes it is true not everyone dies but it can kill you or have serious damage.