In need of Advice, is This normal?

I’m a young male Just recently I’ve begun work experience at a zoo nearby and i had to take of the zoo’s tame cheetahs. They are very beautiful and freindly and I spend most of my lunch hour sitting by thier enclosure, stroking and generally being close to some of the friendlier ones.
Anyway, there are two in particular, a young female, Savannah, and a middle-aged male, Mumba, that have come to accept me. Last time I was there, last week, I was cleaning thier enclosure and stood very still as she got close to me, sniffing the lower part of my body. Thing is, as I stroked her back, I started to have a hard on. I have no real attraction to them, though I am guilty of glancing at their parts when I’m near them.

Has anyone else had this experience? I mean, someone not quite so into the beastiality as I. This never happened to me before and I’m terrified I’ll be staring at them again and someone will walk in on me with a raging boner, and all hell would break loose.

Thanks in advance,

Adam