Heat lamps are not great for ball pythons for two reasons.
Reason #1. Heat lamps suck the humidity out of the air in a ball python enclosure. BP's do not need UV light, and do not benefit from Being given a bulb.
Reason #2. Ball pythons come out mostly at night as they're prey items, Rodents, are mainly nocturnal. Most of the heat that is absorbed by wild ball pythons are absorbed via residual.
UTH's are the better for ball pythons to regulate a hot spot without drying out your enclosure.
As for the infrared, I read somewhere that it's been discovered that Pythons and Boas do in fact have infrared receptors. I'm not sure if they use it for sight or not but they are aware of it, and I suppose it could cause them discomfort (but I really don't know). By the sounds of it he may be more conscious of your presence, than of the light.