Spotting

I spot one day and then it stops for like 2 days but comes back, it's light pink and is kind of like a discharge. I'm currently 5 weeks 5 days. Hcg levels are improving & I'm measuring well. It just worries me since i miscarried last August. I don't know why I'm spotting. Should I be concerned .. My doctor told me not to but I can't help it :(.