One of the greatest risks is integration issues. Trying to square your experience with everyday life. I have experimented with DMT approximately 20 times over many years. It feels like skydiving through time and dimensions.
After 20 minutes you feel 90% normal. It's like having the most intense profound dream. You can have a fleeting sensation of wanting to return to the experience. But it is not addictive in my opinion.
Joe Rogan's given some eloquent descriptions of it. When he says it's like meeting God in a universe full of love, he's being literal. It feels natural. There's a sensation of an intelligence understanding force communicating with you. Making sense of it can be extremely challenging. I'd caution against doing it if you have any hesitation.