No period after miscarriage?

VICTORIA
I had a miscarriage a month ago yesterday. The bleeding from the miscarriage only lasted 4 days. Per the <a href="https://play.google.com/store/apps/details?id=com.glow.android">glow app</a> I should have started my period 5 days ago. But still nothing. I'm having no symptoms or cramps like I normally do before starting. I took 1 pregnancy test on Monday and there was a very faint line. I have taken 2 more since then and they were both negative. I have no idea what's going on. Any help would be appreciated.