Cramping in early pregnancy is normal from what I've read
Its usually a sign that your uterus is growing :)
I'm 7 weeks tomorrow and experiencing the same thing. I read that it is caused by the uterus expanding..
I had alot of that starting around 7-8 weeks and still get them and I just started my second trimester. The books and doctors say its just stretching and growing from the inside. Baby has been fine at all my appointments so I would say it's totally normal!