38 Wks with Moderate Cramps

P

Past 3 days have been sleepless due to moderate cramps keeping me up at night. Cramps dissipate when sitting up or walking around. As soon as I lie down they are back non stop. Lower back pain is constant, bowel movement frequency is nearly every hour (soft stool), feeling nauseous, as soon as an incoming cramp is felt the baby moves more intensely, no mucus plug/bloody show. This is my 2nd pregnancy and didn't feel like this on my first. Has anyone had similar symptoms? If so, does this mean baby is coming sooner than expected? My OB hasn't done a pelvic exam to see if I'm dilated. She said it's not labor pains and more than likely Braxton Hicks. I'm so miserable from lack of sleep!