first off, congratulations!
secondly, it would be in both yours and the babys both intrest to talk to your doctor about your concerns to avoid a miscarriage this time around.
your doctor would be the best person who could address your concerns and give you helpful suggestions.
pain or cramping is ok as long as there is no bleeding that goes along with it.
if you feel really concerned with this pain, then go see your doctor. Again, he or she would be able to address your concerns better than anyone on here, dont diagnose yourself through the internet hun.