Mucus Plug?

So, I am no stranger to mucus during pregnancy. I have had cervical mucus and such my entire pregnancy, but it has always been clear or slightly yellow. Today I wiped and was greeted with a green glob of mucus. Very light green, but definitely green. I called my midwife and the nurse said my midwife would likely want to do a culture, because it is more likely to be an infection than my mucus plug. I have zero itching, no odor, no discomfort other than occasional mild cramping. I haven’t had any infections my entire pregnancy. This is my first pregnancy, and I definitely don’t know more than a doctor or midwife...but what are the chances? I am 33 weeks today. Has anyone else experienced this? I just feel like it’s not an infection and would hate to waste a trip to the doctor. Sigh.