Hi, yes I had the same problem in my second pregnancy satrted at 32 weeks, he came early thankgoodness and in my last baby is eight days old started around 37weeks, it does feel like morning sickness and I also found that sugar helped a little.
WARNING WARNING TMI
 I also had the stomach cramps, I thought that I was going to have the runs but when i got to the loo urgently it was normal consitency just lots. Sometimes just cramping though!!! Poppy came a week early so lasted around 2 weeks. Good luck, bubbie is'nt far away!!!!