I wouldn't call any of those things bad at all, but if you want to get even better at art you could ask for tips from people you know are good at those things! Recently Alexis posted something(I forgot what it was about but that's not important at the moment) and she did some really good foreshortening in the arm, so I asked for some advice and she gave some really good advice! So, yeah, just ask around for tips and advice, and you can really level up quickly!
Your art is really cute right now, but with study and practice you can become even better than you are now!