You don't have to have a huge set up. Just set a few small objects next to your computer and you're good to go. (That's what I do, usually. It's less than a foot of space all the way around, but that's enough room to have an apple or a glass or something.) Still, though, the eyedropper method does work when working from photos, too. (It's all down to personal preference, really.)
The sketch from life looks pretty good. (Aside from the two small things you mentioned - her nose does seem a bit long to me and the hands a smidge too small, but it looks fairly nice over all. Good job!)
Nice eye studies. Looking much better!
Samurai is looking pretty good so far, too.
And that doesn't sound stupid at all. Hell, before a few years ago, the closest I came to drawing was maybe scribbling abstract squiggly lines on the edges of notes I was taking in class. Never drew anything otherwise. No one-off comics, no little doodles..nada. (Well, outside of maybe doing some crayon work in elementary school. LOL) One day I was looking up some artwork I had seen in a video game and I came across this site. I was so stunned by some of the things people had (supposedly, because I couldn't believe they had) drawn/painted that I was like "No way. I need to do that." 0.0 And, so, for the first time I actually sat down and tried to draw something. It was awful, of course, but it was a starting point, and the rest was history. (I just starting my third year of drawing as of this past June, I think. Man, time flies!)
Everyone has their own story and I say all the above not to necessarily to showcase my own story, but to illustrate that here's no set time frames for how quickly you should arrive at certain bench marks. You can do something your whole life and still never be 'good' at it, you can do something and pick it up quickly in a week's time and be amazing at it. I like to think about that whenever I'm feeling discouraged about my own progress or, sometimes, even when I'm enthused about a breakthrough I've had - it kind of helps ground me a bit and bring me back to a frame of mind where I'm ready to keep working. Time is sort of irrelevant in this field -- no one cares about how long something took to create (or even the years you put in to get to that point), it's all about the end result.. That nicely polished, finished piece that you put out there. In the end, time really doesn't matter.. (Well, unless you're not using your time wisely. Because then it just becomes about how you're shooting yourself in the foot and postponing your own success. XD But that's a whole different discussion.)
Like, I knew this one girl - she lived on my street throughout my entire K-12 school experience. She was known as 'The Artist' in school. She was constantly drawing. She drew on anything she could get her hands on. (Even desks, occasionally, which really ticked off the teachers XD) She cartooned. She'd try to draw people. She'd color.. Art was her only interest and it was all she ever did. She eventually went to college for it (and graphic design, too, I think) and they gave her a degree.. And now she works behind a desk at some kind of office job because her artwork just really was never up to scratch. Now, knowing what I know about the industry and about general standards for what is marketable.. I look at her current portfolio (because she has it online still) and I can clearly see her artwork style never evolved beyond the skill level of cartooning that she had in 6th grade. (It looks exactly the same. Seriously.) She clearly never seriously did dedicated studies, she never tried to grow or train herself to expand on her skill set. She kept hiding behind this wall of 'well, I want to do kids books and that stuff doesn't really matter because it's just cartoons'. (And her teachers should be absolutely ashamed of themselves. But, as I've heard Daniel Warren say on his streams from time to time, schools don't always teach you the things you should be learning when you're doing art and sometimes you have to do it yourself, instead.) She just kept getting patted on the head and sent on her way, and she was fine with that. She never tried to accomplish more than that.. And, so, she never did. Spent her whole life doing something only to do nothing with it in the end. (Now, if she wanted to put in the effort and try to learn color theory and maybe some anatomy to help bump her skill level up, there's nothing to say she couldn't pick it up and run with it. But, from what I've gathered, she just can't be bothered. It's a shame, really. Actually, in all honesty, it kind of makes me kind of want to slap her for her laziness. XD)
Anyway, long winded stories summed up: Art is friggin' hard. It takes a lot of dedication and hard work and every thing you accomplish is something you've fought for. You can't focus on where you aren't, you just have to focus on where you will be. As long as you're working towards improving, you can never go wrong.
Aaaaand.. apparently I'm in a chatty mood today. Sorry. XD