A bit of context:
Exhibit A) I wrote a poem that had the line "crystalline crystal lines."
I googled this phrase, just to see if it was out there, and I saw that it was. I had never read the poem in question, but I still felt like I was in dangerous plagiarism territory, so I ended up using another phrase instead in my poem.
B) I wrote a poem in which I had the line "synonym synonym synonym synonym." I googled this phrase, and I saw that it was used several times (in a non-poetic genre, in a scholarly argument and a news article).
I also used the phrase "reading the Cliff's Notes of Hamlet" and I saw that someone in an online discussion board used this phrase. I used the phrase "sword-wielding protectors" and this appeared in several hits of fantasy novels and forums. Same with the phrase "kaleidoscope galaxies," and "children of the atom," which is the name of several comic book series. In a poem I mention the movie finding Nemo, and say that "he's a fish who's been separated from his father." I found this quote in a scholarly article about the film. In all these cases, I hadn't read these sources at all, or even heard of them. In all of these cases, I have felt uncomfortably close to plagiarism, and have altered my poems.
What do you all think?
Am I being oversensitive and paranoid because I'm not the first one to come up with a certain phrase? Or am I doing the right thing?