PIO injection site burning?

JT • 5 yrs 2MMC, 1CP... delivered #1 and #2!!!🌈 🌈

I’ve been doing PIO shots for a few weeks and other than some numbness, bruising, and the initial pain of injection, it hasn’t been too bad. Tonight, though, about two hours after my shot, the area around the injection site is burning/stinging (feels like an area about the size of my fist). Has anyone had that happen? And what can I do to make it stop?