It might have been a combo of all of this or just one-feeding a possibly off mouse, handling/moving during feeding, way too hot of a hot spot, 90-92 max so yes that was quite a bit too warm. Don't feed him at all for several WEEKS-he needs time to heal. Feed 1 smaller than normal meal when you do. Get your temps 100% on point, they need to stay steady if you want a healthy animal. Feed him in the enclosure, there's no need to move.