Oh my god, I love doing grid art work (even though I usually end up just like "oh, **** this" and draw with the ref, which makes it look terrible.)
My art teacher last year said to take a break every so often so you won't be burnt out or overthink how it looks. I love listening to people on youtube when drawing, but that may be just me. WhenI did one with HABIT, I got mad because I overworked and only had the TV as background music. That resulted in me ripping the art, even though it looked great the next morning. another tip, which I do for everything with art, don't forget it's just for fun. It's not going to kill you to make one mistake or shade something wrong.
Also, if you ever have to enlarge the image (it looks like yours is staying the same) please, for the love of god, only draw one grid at a time. I ended up with a
very deformed hamster once