Hi Prosaix! Thanks for attending the critique night Here is your feedback
FIRSTLY, wow, what a great concept! However the smudge which is the end of the tub in the background, is a little distracting, maybe consider rubbing that out?
The focus is nice, but many would like to see the needle tip in focus too, to give this some kind of emotion behind it possibly. And possibly focus more on the forefront heart too. Having the background brighter white, like some of your other pieces, might work well too.
The shadow of the back wall detracts from the image a little, the vertical white section. Having a more seamless background might work better here
Like you, yourself, said - using a higher aperture might have worked better here too.