Honey, I lost the baby!

My poor baby girl. She is in the process of moving to a "big girl bed", and last night I lost her. Every night I stay beside her bed while she falls asleep. I know, I know, bad habit to start. But how else can I get her to stay in the bed long enough for the sandman to hit? Anyway. Last night, when I got up with Boy terror for our regular 3 AM feeding, I checked on her, and she was fine. I was so proud that she hadn't slid sideways, and was still all tucked in. Her bed so far is just the mattress on the floor, so she can't fall far, but I don't want to think of her all cold on the floor!
At 6:45, there was an earpiercing scream of terror. I tore up the stairs and into her room, but it being still dark and all I couldn't see her in the bed. I started doing the cooing Mummy thing, you know, "it's okay...it's okay. Mummy is here. It's okay..." but it wasn't okay! I groped all over her bed, but I couldn't find her! She was still screaming, now with a slight touch of hysteria in her voice, and I was practically shouting "IT'S OKAY!!! IT'S OKAY!!!" Finally I hit the light switch. AGHHHH! No little girl in the bed! I shouted "lovebug!" and for a few minutes we went back and forth "lovebug!" "MUMMYYYY!!" "lovebug!" "MUMMMYYYY!!" Finally I spotted her. Apparently she had slid off her bed after 3, and rolled under her the crib that is still in her room. When she woke up, she couldn't sit up, so of course she panicked. She was trying desperately to crawl towards me, but she kept getting stuck between the wall and a crib leg. Silly me, I never thought to check under the crib. I just am not at my most clever at 6:45 AM. We have never before had to do a "Marco Polo" search for each other (remember that game from when we were kids?). It is not a large room. Yet I somehow was not able to locate one screaming child. God help us all if we ever go to a mall.