Nope, that's typical. I looked up the data a while back. 1-2 weeks is the general timescale for developing dependence and for withdrawal. Once your neurotransmitters reset, you're pretty much back to normal.

I don't think 3 cups is that much really, except maybe if they're all Starbucks Venti brewed coffees. If you drank more quitting would be harder.

No, I don't think it is atypical; that's what quitting caffeine is like for me, too. There are some people who have a terrible time, though.