My high risk Makena mamas and losing their mucus plug

I've had 2 early babies and very early labors so far. This will be baby number 3 for me. I'm currently getting Makena injections for my preterm labor. But I started having contractions the other night, went into er and they stopped. But the past 2 weeks I've had period type cramping off and on, and what I think may be my mucus plug I've been losing for the past week in a half now. I've never had Makena, but my er dr. Was pretty sure its just discharge from my injections. Sorry for the graphic pictures. I'm just concerned and don't know if any other Makena mamas had this and if it was normal for them. Thank y'all!