Natural muscle relaxers!?!

Hey there - long story short; I have a history of kidney stones but have always been able to pass them within 48 hours with the help of nuclear relaxers now that I'm 16 weeks pregnant and trying to pass one I'm not allowed to have a muscle relaxer. I'm going on 4 days trying to pass it now - anything food wise or herbal I can take to relax my muscles to let it pass???