I’ve been trying a chord progression recently
Although it’s a little different, it feels like you can sing it down.
So what should we rely on to determine the chord in this case?
Or is there no fixed chord at all? Just look at your choice!
Or should we use more musical instruments to determine, especially when people’s ears are tired and can’t only use the piano?
Yes, I think you should sing it, and share your song with us 
As for the instrumentation, I often do this, taking the same chord progression and express it with a sustained pads/strings, or with an arpeggiated key sound (e.g. piano), or (synthetic) guitar strumming. Even using different melodic/arpeggiated expressions of the same chord can make a difference in how the chord progression sounds (especially depending on what note of a chord is truck last in the sequence, ahead of the next note of the next chord).
Just my own observations, I am by no means well versed in music theory.
I’d like to sing it, but it can’t be uploaded here. Ha ha ha
I found a way to be more accurate in Cmaj and Am
After finding it, I’ll change the tune as needed
