Many people will find that they feel tired or relaxed after orgasm. It is the way our bodies are wired. And there is nothing wrong with that.
Multiple orgasms are possible. And they happen. But not to everybody. It's not a big deal, either. There isn't anything "wrong" with you if you can't have multiple orgasms, or, orgasm more than once per day, even. It just means you are wired slightly different from someone else (you don't have to believe everything people say either. There are plenty of inflated egos out there, and plenty of people who tell the truth )
If you try to pleasure yourself when you just don't feel like it, it won't be a ton a fun, and is a waste of your time.
You may read this if you like. It may give you some more information about orgasms, etc:
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