Drama Drama

I am in some serious need of advice.
The basic question is i guess: How can i not suck as a parent?
More specifically, my precious little two year old has done nothing but fuss for about a week. She is queen sassy-pants and says some things to me that are rather shocking. For example:

Elliot dumps all her markers out on the carpet.
"Elliot can you pick up your markers please?"
"NO! Mommy, you do it!"
"Mommy didn't make that mess, honey, can you pick them up please?"
"Mommy! Clean it up!"
"Honey, if you can't pick up your mess, the toy monster is going to come and take your markers away. Can you please pick them up?"
"NO! (screaming fit, followed by a bump on the head from tripping over her feet in the midst of tantrum.)"
The toy monster took the markers away.
Something similar seems to happen every couple hours or so when i'm home with her.

Really. what on earth am I doing wrong?!?

And then there's the food issue. I know a million other parents have gone through this same thing but i'm getting concerned about Elliot's diet. Or lack thereof. She hardly eats, and hardly ever eats what I make for dinner. I know it's probably my fault because i'll give her peanut butter sandwiches because i don't want her to starve, and she snacks on way too many unhealthy things. I'm trying to move away from that, and i haven't bought fruit snacks in about a month, but still...
I don't know. i'm just frustrated with myself right now. Boo.