Spotting at 5 weeks 5 days

So, I've had mild cramps off and on since I got my positive test (little over week ago). I noticed spotting about an hour ago but it's only noticeable when I wipe..it was first bright red then turned to light pink. I've had a pad on for an hour and it hasn't gotten anything on it.

Has anyone else experienced this? Is it normal or should I be worried?