Just wanted to let you guys know what happened to me.... At around 34 weeks I had a big fall straight onto my belly - I was going to fall in the pool but as I tried to get my footing I fell straight onto my belly & hard. Same as you both I panicked! I went straight to the hospital & had monitoring done to make sure everything was ok. Essentially the hospital said bub would be fine as Alan has said, the only concern would be if there was an issue with the placenta detaching & in that instance you'd have bleeding as a symptom.
Try not to worry about bub, as hard as it is I know, but they are nice & snug in there so thy probably hardly felt a thing, just mummy being worried ;)