i forgot a song and i'm going insane

so, i just started learning the piano and i learned about the D position. I don't really know the notes but i know that it is a D and it's right before the middle C, so i guess it's called D3? I don't know. and the app shows this scale that starts in the D3 and i just have a sensation that this is a song. i feel like it's pretty well known, like a nursery rhyme. it goes like this: D, E, F, G, A, G, F, E, D, E, F, G, A, A, G, F, E, G, F, E, D, D, E, F, G, A

at first i was sure that this was a real song, but i asked and no one knows what it is. i also tried asking chat gpt and humming it to google and youtube, but there were no results. at this point i don't know if it's just the scale that looks too familiar for some reason or something. I NEED TO KNOW

is this real or am i imagining it? please help