My professor said my sources are “too recent and too perfect”, now I’m worried it looks suspicious

I just got feedback on a research paper and one comment stood out. My professor said my sources were “unusually recent and very well aligned with each other” and asked how I found them. Now I’m kind of stressed because I didn’t do anything weird. I just used my school’s database and filtered for newer articles so my paper would be up to date. I also spent a lot of time making sure all my sources actually supported my argument instead of just throwing random ones in. I didn’t use ChatGPT or any AI tools to generate sources or anything like that, but I’ve seen people say that having “too perfect” sources can raise red flags.

The professor didn’t accuse me of anything directly, but the wording is making me nervous. I still have all my tabs saved and notes from when I was researching.

Is this something I should be worried about, or are they just asking out of curiosity?