How long after Miscarriage did your period return?

Angelica • Married mom of 4 girls. My last daughter was born unexpectedly on 8-6-15 preemie @ only 26w2d.
I had a chemical pregnancy on Nov 29th and skipped the whole month of December with no period and now it's already January 13 and still no period or signs of it coming... Read online it could take anywhere between 5-7 wks for it to return and I'm at the 6 wk mark now. Should I continue waiting for it to come if it ever does? Or should I call Dr and see what's going on? Still would like to hopefully conceive again someday. Thanks for any advice or opinions, very appreciated!