I LOVE that you did it YOURSELF!
It is a nice size too. After you brace it, here is one more thing you may want to do.....rub clear deoderant on the bottome 12" of the 2x4s so she won't chew on them and get a splinter stuck in her mouth, throat or stomach. You can use the deoderant on other items (like bottoms of kitchen chairs) that you don't want her to chew on either. HAVE fun with your new baby!!!