castor oil is just going to make you **** alot and in turn gives you contractions which can or cant kick start labor, but downside to castor oil you consume baby consumes and baby can poop in inside sack and can get meconium which is really bad for babys lungs
If they are coming frequently time them...definitely call your doc as well and let them know...sounds like the real thing but never know could just be getting you ready. Good luck!