Where does the apostrophe go?

Okay, so I have been told that I am using my apostrophes (is that one right?) improperly. The rule: put an apostrophe before the s if it is possessive. If it is not possessive, just add the s. Is this right? I have made some changes - please feel free to let me know if there are any other grammar issues I am having. :) I apologize to anyone else who has been bothered with my improper grammar. I expect a comma lesson soon. Just kidding mom, I love you!

I used to have a baby...

Now I have a little girl. We are less than one month away from being 2 years old and my buddha is no longer a baby. The terrible twos have been much less stressful than I anticipated. I know she is not technically two yet, but in her head she is already 12. She is talking up a storm and has a gift of making those around her laugh. Mimi says she's going to be a 'megavert' like her mommy - apparently this is a step up from an extrovert, but I see so much of her daddy in her. This week she was standing in the corner playing hide and seek and counted to 10 as if she had been doing it for years. Greg and I both looked at each other in shock as she did it over and over again. It is all going by too fast and I am looking forward to our summer together. 6 weeks left! The warm weather gets us all itchy for some time off. Anyways, that is the quick update here. I'm sure there will be more soon!