Try not to stress darl, i was told that #5 was going to be 10 pounds or more as i was quite big and measured 3 weeks bigger than my dates, well he came 2 weeks early and was only 8 pound, which is very normal for me.
I had severe spd and was told that because of his size i may need a c sec, i did not want one, and am so glad that i did not need one.

Sometimes they are wrong.