Bouncing Baby and Back Pain

Interesting title for a blog post but it perfectly sums up my day today.
Bouncing baby:This baby moves but it is so different than with Ellery. It is always so low and its never very hard (dr says because of my anterior placenta). It also never seems to happen as much as it did with Ellery. But tonight he/she started to move and it was actually hard enough to notice my belly bouncing up and down. I called Ellery over to watch it and she put her hand on my belly and BAM her hand flew off my hand. Baby literally bounced that high. The best part was her reaction: her eyes got wide, she looked at me confused and when I smiled to show her it was ok she laughed and said "The baby is bouncing in there!" Then she tried to "hit" the baby back, thinking she was playing a game, but I had to explain that the baby isn't trying to hit her but just say hi. It was just such a cool moment to see in her eyes.
Back Pain:Now the not so fun part of my day. I have HORRIBLE back pain at the moment. Honestly, it is almost making me feel like I am in labor but without my stomach contracting (I checked a few times to make sure it wasn't getting hard). I tried laying down on the floor...BIG MISTAKE...I almost couldn't get up. I actually had to roll to my stomach to get up-I was like a turtle. The I tried sitting on the floor and that was also horrible. I just feel like all my weight is sinking into the back of my hips and it hurts. So the only thing I have found to help is to lay on the couch with a pillow or rolled blanket under my lower back. Once Ellery goes to bed I will be searching for our heating pad to see if that helps too.