Yes! And they feel like little grains of sand

My PN problems the same. won't heal until white core comes out. Lesions can get quite large and are painful. Picking at them will make it spread, so try and limit picking at them and be patient. I cover the sores with round bandaid and use 3 different strengths of steroid creams, depending on which cream works best for that sore. If you do this constantly for like a week, the sore will look better. I also use Cordran Tape quite a bit. Especially for ones on my face.

Yes. White cores. And some are like hard crystals. My soars will not heal until all are removed.

I think the nodules look like little volcanoes wating to erupt they have a spout/hole at the top where the lava discharges
that's just my opinion-observation

YES! I have been saying this to my doctors all along. So frustrating.