You have a pleasant voice. Do not know the song which in a way is nice. You have a rather light and steady tonality with a consistent presence, which is good.
The only thing I can think of, I guess if there was a key word of what I'm thinking, it's 'dynamics' in general. There are quite a few options of doing this:
Add more 'emphasis' on syllables
Pull/push timings a bit from metronomic
Using a slightly weightier tone for more emphasis.
Fluctuate volume slightly more
Dynamics, not necessarily pitch dynamics (which so many people seem obsessed with, lol) but dynamics in general for me at least would push you over that edge. Go from what is a pleasant pop song, to something that could really, dig into you as a performer. Don't be afraid to be a bit selfish and revel in it.
Shyness could make that tough, but there is a flip side to shyness, and that's bottled up things we have trouble expressing. Music can be an outlet. I believe in you. You're already doing well. Keep at it.