What does he want??? Mixed signals

Bill and i were friends for years. One of us was always in a relationship but there was always flirtation between us. A few months ago we both became single at the same time. We went out a few times in groups and the sexual tension was totally obvious. He started emailing/calling me a lot. He talked about very personal things. He told me that he liked me on an emotional level (whatever that means) as well as being hot for me.

So flash forward to last weekend: We finally hooked up after a night of drinking with friends. He said he loved the oral sex (he said I was a 9 1/2 on a scale of 10). That was as far as we went.

Then about ten minutes after, he said "I don't know what to do because you're not the kind of girl you just throw away when you're done with."

What the hell does that mean??

He called the next day and didn't even mention the hook up. But he asked if we could hang out next weekend, just the two of us. (I can't b/c I'm busy but I suggested the following weekend.)

Now his emails are totally different - all flirtation has stopped. He talks about work, weather, pets, etc. But yet he's eager to confirm plans to go out in two weeks.

I'm so confused. What does he want? If he wants more hooking up then why isn't he flirting anymore? Does he possibly want more than that?