I'm thinking of trying nitrious oxide for the first time?

Ok I've done allot of research and I'm curious to know what to expect. I know to do it with a cracker and a balloon deafantly do not Inhail directly from the canister so I know how to do it safly. It won't be something I will do every day maybe once every few months or once in a while but when I'm sitting in bed once I'm in bed and I Inhail the Ballon what should I be expecting.  I'm a bit nervous tbh