Real confused about fillings

I’m a 2024 graduate general dentist. I’ve done a lot of fillings being a general dentist and I usually get the occasional follow up pt for post-op sensitivity after class 2s, just like most providers get. Due to what the office supplies we have, I’ve been using tofflemire and plastic wedges for the majority of my short career. Recently tho, we ordered some Pro-Matrixes to try out and I like them a lot. I’ve also started pre-wedging my class 2s to create separation. With these two changes, I’ve had better contacts then I ever had with tofflemires (those were honestly hit or miss 50/50s). But for some reason, ever since I start using the Pro-Matrix and the wooden wedges to pre-wedge and close my matrix at the bottom of my class 2s, I’ve been getting A LOT of follow ups for sensitivity. My cavity preps are closed at the bottom of the box, I always check before filling. I’ve kept my bonding, etching, and filling protocol the same. Recently I’ve started doing two layers of bond as suggested by another doc in my office and I’m waiting to see if I continue getting this sensitivity.

I wanted to see if anyone can help me figure out why this is happening? It’s really a slap in the face seeing so many of my filling patients come back and it eats so much time bc it takes chair space and I’m redoing the fills too. If anyone has any idea why this could be happening , please help lol