Help me get better?

I wouldn't say this is finished by a long shot but I can't help but feel as though there's something off about the image as I am trying to draw it. Not sure if it's a lack of understanding for shading and line work or if I'm just getting in my own head. I have the reference attached as well but any advice or maybe mild reassurance that I'm not practicing in vain? I'm 30 and have been slowly getting back into drawing over the last couple years, just recently got into drawing people.