First PP period

Hi all. I’m 15 weeks pp and I’m on day 20 of my period- first one since giving birth. I’m EBF but my LO went on a nursing strike for a couple days a few weeks back which I think was what brought it on. Also, I got it a few days after getting the Mirena IUD put in which my OB said would most likely delay my period also. My period has been super light but as soon as I think it’s going away (brown blood) it comes back bright red again. Going to call my doctor tomorrow but wondering if this seems normal.