Weaning

I’m currently in the process of weaning my 15 month old. He was eating 4 times a day and I cut them down, but rather rapidly following the schedule from ChatGPT. My last feed was Thursday night. Now that it’s Saturday, my left breast is so swollen and engorged. It’s very hard, heavy, and uncomfortable. It’s painful to the touch. Is this normal? I’m so scared that I’ll get mastitis. How much should I be hand expressing? Do I need to pump at all? Please send any tips!