Mucus plug?

I’m 20 almost 21 weeks today and on 2 separate occasions I’ve had discharge like this. The second time it was a much smaller amount but nonetheless it was sticky. Everything I’ve looked up says it could be my mucus plug but I have no other symptoms of premature labor. No cramping and no back pain and I’m still feeling flutters In my belly. We just had our 20 week ultrasound and everything is looking perfect. The only other symptom I’ve had is a bit of pressure here in there in my lower stomach/uterus. I don’t wanna have to go in for it to be nothing and I don’t have another appointment for 3 weeks. Please help me I’m worried