Have I dug myself into a hole?

I'm considered one of those nice people. Always polite, looking out for the other person and not myself, and generally like everyone to be nice and compatible. I don't think I'm necessarily a door mat, but I certainly like to keep the peace.

Miss Lillie at 21 months has started to become very demanding. She has a sense of how she wants something, what she wants and when she wants it. And, when she was younger it was always easier to appease her demands, because they were easy to do. Certain songs in the car, needing a pacifier or milk. As her vocabulary grows and she learns more about her environment, I think I might be getting pushed around a bit by my baby. And, I'm wondering with all my peace keeping abilities, have a dug myself into a parenting hole?

I know the terrible two's have started early in this household, but I just don't know how I'm going to get myself out of this demanding phase without meltdown after meltdown. When Lillie doesn't get her way it usually starts with fake crying. Then very loud no's and foot stomping. And if you're really lucky, jumping in the air and landing straight on her bottom. Distraction only works about 25% of the time. So, how can I let her think she has gotten her way when she hasn't?

I guess I should scoot myself down to the bookstore to find some terrible two's parenting books. I'm sure it will have all the nicey nice ideas like time out and things that really don't work for this age. Or, I may just keep on being a pushover to save myself from the crazed baby state. Any advice is welcome, I need it.