Mucus plug???

So I am 38 weeks and 2 cm dilated and 80% effaced. I was having really bad cramping and irregular contractions today. I had my cervix checked on Thursday so I was excepting some discharge but I didn't really get much. Either way yesterday about 6 hours past the 24 mark of my check I noticed a lot of mucus discharge. It wasn't anything too big but it was noticeable and was starting to just fall out as I was going to the bathroom and went to wipe. Me and my fiancé went grocery shopping and was walking around for a few hours and at like 10:30 or so I went to the bathroom and in my underwear there was a big globe of mucus. It was like the size of an egg. I was freaked out. Is this it, is this my whole mucus plug? I'm kinda just curious if I completely lost it or not.