If you had to buy any of my artwork which one would you buy and for how much?

i would like to buy
Fairy watercolour 1
for 100 dollars, seriously
its so amazing!

I would either buy the randomness one for twenty or so because its well drawn and colorful or the ceil phantomhive one for a friend of mine at whatever price she says so.

You're asking the wrong person.
....Or more accurately, the wrong person (me) is answering this question. You probably shouldn't read this response in complete honesty.
I don't buy artwork. I'm a huge art critic on everyone, including on myself. Honestly, I wouldn't buy any of those. They all seem unfinished (not because its in pencil, in fact I love traditional, just because the quality and detail isn't high enough for my standards) and a still improving student artist. I know you can draw better than that, though I'll agree your pictures are nice. I suppose, your "Mario flower: evil" picture, because I like Mario stuff. It also looks pretty and I like it. I would buy that for $5 because I'm a cheapskate with no money. Take it or leave it.
Your portraits are also nice but I really don't give a damn for portraits. Depending on the people, it'll probably be highest around $10-20. Art just has too many competition and people can find good deals with $5-20 for high quality sketches.