Visiting from M15. I'm 39+3 today. I've been losing pieces of my plug for weeks now and finally lost more or less the whole thing last week and still no baby. Your mucus plug regenerates. Losing your mucus plug doesn't mean anything really. You can lose it weeks, days or hours before labor begins. GL.
There was a thread about this just recently saying they can regenerate and a lot of ladies lost theirs and didn't end up in labor for weeks. Search for the thread I'm sure it'll help give you reassurance
Re: stm mucus plug scare