L.G.
Everything I've seen and heard indicates that if your vehicle was damaged, there may be a chance the car seat was too. I'd check with your insurance company. If they'll cover it, go for it.
The State Police told me to replace the seat when my husband was driving our car and his car was hit by two cars following their collision. His air bags did not deploy and our son was not in the seat. My husband was sitting at a red light and the two vehicles slid into him following their crash.
There may have been damage done to your seat that you don't know. It has to do with the laws of physics (an object at motion tends to remain at motion, an object at rest tends to remain at rest...). Your car may have been going only ten mph, but if you hit something stationary, the force is considerably stronger than 10 mph. If your child was in the seat, then the stress on the seat was even greater.
I'd check with insurance. If they'd cover it, get a new one. If the seat was damaged (but not able to be seen by the naked eye) and you are in another accident and the car seat fails...
it is a scary thought. Here's hoping insurance will cover a new seat for you!