I'm recently 18 weeks and when I was around the 6 week mark I thought I was going to start my period, turns out false alarm I was pregnant. Anyways, my doctor told me its just your uterous expanding to make room for baby! I'm petite with size (5'3 120) and I've had abdominal cramping not just in my uterous, its nothing to be concerned about unless like they all said it becomes unbearible and there is bleeding. You Got this girl!
Im also 6 weeks, I have cramping too.. as long as they dont become unbearable and as long as there is no bleeding everything is fine! It just means your uterus is stretching(:
I was told that light cramps is normal. As long as there is no heavy bleeding. You may also spot. But as long as there is no heavy bleeding you should be fine. But to ease your mind it wouldn't hurt to call your doctor.