Bleeding after exam

I know it's normal to bleed after having a cervix checked and last time I was checked (35 weeks) I had spotting for a few hours but it was like pink. This morning I got checked and was completely effaced and 4 cm dilated and since then I have had terrible bleeding and have been having period like cramps. Also when I wipe there are like chunks of blood (tmi). Could this be pieces of my mucus plug coming out? Should I be concerned about the amount of blood or is this only happening because I'm farther along in my pregnancy (38 weeks).