Is it normal for overexcitment to cause anxiety?

Well I'm supposed to be meeting up with someone I haven't seen for aages and at first I was excited. As time went on, and reality set in, I started getting some anxiety. Now I actually can't wait to get it over with, because i literally have sore ache type feeling in my stomach. Its so painful and I guess its from intense nerves !? Is this normal and when will this pain go away? I've had it for couple days and no improvement ...:(