Nope, no rock in that one. Just a nice looking normal.
You said that he/she struck at you during/right after feeding. Any more strikes since then? Any hissing? You say you were doing maintenance when you put the thermometer on him/her. Does not look to me like you have an aggressive snake at all. Just a hungry one. Set up distinct parameters when feeding: a tap on the left wall, offer immediately after opening the door; you decide but always follow the protocol and you will soon have a snake that knows whether food is coming when you open the door or not.