You shouldn't be worried unless You start cramping severely and bleeding bright red heavy. Otherwise it's normal. I'm almost 8 weeks and I barely cramp now but I was when i was 5-6 weeks.
Some light cramping is normal i had that at 6weeks and i also had light spotting a lil bright red spotting for about a week i tryed my best to rest and not carry anything heavy or stress just relaxed im now 39weeks but if ur cramps are bad and u start bleeding heavy go to the e.r it could be a sign of a m.c