Probably not the humidity, some young ones are just more defensive than others. I'm assuming its a baby since you said a 10G tank. Typically they'll grow out of it.

I have a male normal that has literally tagged me 95% of the time I've handled him, just the other day I took him out and was "praising" him for not hissing at me then as soon as I was setting him back in his tub he got me on the hand.