I thought I had regular PMS this cycle but there were a couple clues that it was different that I didn't pick up on at the time (these symptoms were around 10-15 day dpo):

Breasts didn't start to get less sore as AF approached

I was more bold in expressing myself, to the point that I was off-putting to others

My uterus was swollen which I only noticed because I've got a large fibroid and I can normally feel my uterus because of it. I was feeling a bit down because it felt larger and I thought that perhaps my fibroid was growing but it felt too squishy and I was confused.

When I was a day late I started having some odd itching on my right forearm and I started getting these tiny pin prick like itchy blisters on my hands and forearms. I'm still getting those and it seems like it is connected.

I felt good for a few days and then I had a lot of cramps that first week when my period was late so I kept thinking it was coming, even after the + HPT and blood test. Progesterone supplementation helped keep the cramps in check.