Oh no, that must have given you a fright!
I read a section in WTEWYE just today that said baby is very well cushioned by 'the most sophisticated shock absorption system in the world' and that to penetrate it, mum would need to have sustained injuries that would likely land her in hospital.
However, if you're worried, there is absolutely no harm giving your doc/midwife a call to put your mind at ease.
Take care, hope you're ok xx