Dude, don't worry about it so much, I know exaaaactly how you feel. you and I have the same problem of thinking too much and too hard about these sorts of things, and all it does is make one frustrated and/or depressed. Who cares if you can't find something unique or special right now? That's not why you started drawing, and that shouldn't be your focus, cause then youre overthinking it and will guaranteed come out contrived.
Sketching helps of course, and as do studies, doing activities and challenging yourself, all of which you're doing, and doing right. If there is anything on top of that that I would highly recommend its experimenting MORE, try to find a different method of doing what you do, if you cant find a different subject or something like that. Hell, try some 3D, switch up mediums, when you do the same thing day-in and day-out you stagnate, no matter how good you get at that one thing.
Im seeing some nice explorations in these sketches, some very familiar studies, and a few examples of trying far too hard.
Set aside a new sketchbook and designate it for failure. Go to a coffee shop/pub with the most unwieldly tool you have or can make that can make a mark on paper and have some fun. Just find a way of putting pressure off of yourself to imrpove/make good art/be unique/be like miyazaki/otomo/whomever and you'll have fun with it again.
Or at least that's how it works for me.