First time mom- first ultrasound questions!!!!

Okay, so today I had my first ultrasound and I am exactly six weeks! At the time of the ultrasound, I was still in shock about being pregnant, seeing the heartbeat, etc. this is my first child. I forgot to ask my doctor if everything was normal. So I am asking you ladies, is 0.38 cm normal for a fetus at 6 weeks? The heartbeat fluctuated between 84-118 Bpm. 
I'm sure I can call him tomorrow and ask but of course I can't sleep. Any information will be greatly appreciated!!!