How have I gone from being a frigid maiden to a raging nympho after one week with my first guy?

A guy I work with asked me out last week. I wasn't really interested. I've never been interested in men. He is a junior partner in the business, so I thought it might be worthwhile, just meeting him for a pizza.

He's so incredible, I fell for him straight away and it appears to be mutual.

After one week, I've turned into a raging nympho. I can't wait to get layed.

How could it have happened? Is it any way normal?
How have I gone from being a frigid maiden to a raging nympho after one week with my first guy?
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