There are people on this site who have been really messed up, long term, by psychoactive drugs. (Not psilocybin specifically, but it could probably have the same effect.) I had a friend who was badly affcted by a single bad LSD trip, though fortunately he eventually got over it. As Forest Fire advises, if you are going to take psych drugs (of any kind), it is wisest to do so in surroundings in which you feel comfortable, and with at least one person you feel safe with and can trust. Two would be better, in case the trip goes in an unexpected direction and they need to restrain you. ( Just because you are convinced you have wings and can fly like a bird, doesn't make it a good idea to launch yourself off the top of a building.) You should also wait until a time when you are in a good mood (or, at the very least, not in a depressed state). These are powerful drugs, and you need to treat them with caution.