Sorry to hear about the pain Kay, I've been forced to sleep funny because of the dogs on the bed as well so I know very well how hard it can be. It almost sounds like you pinched a nerve or something which could explain the shooting pains and such, but I'm not a doctor so don't take my word for it.

And take it from someone who has two small dogs sleeping with them it doesn't make it any easier to sleep in fact it makes it harder because there's the whole squish factor and well if you have a dog like Beaker they still stretch out only under the covers at the same time.