No, it’s not wrong at all to write about things that haven’t really happened to you! Imagination and creativity are some of the most important ingredients in writing, and sometimes ”deep heart-wrecking love poems” have to be written from someone else’s experience, because everything in them may not have happened to you.
While plenty of things I write are from my own personal experience, there are also plenty of things that are not. Almost every single writer has written about something that hasn’t really happened to them. You’d be hard-pressed to find a writer who has stuck entirely to the facts.
There is absolutely nothing wrong at all with writing about things that haven’t happened to you. Unless, of course, you were writing a memoir or something and completely lied about your experiences just to exploit people and earn money. But writing about things that haven’t directly happened to you in poetry or prose is perfectly okay, so long as you don’t lie for profits or purposes of exploitation. :)