Why am I so crap at waiting?

So. 38 weeks, 4 days.
Why am I so crap at waiting? I'm so impatient. This is all because I had William at 37 weeks. All throughout this pregnancy I thought minicookie would be early. Once I reached that 37 wk mark this time around, I've been expecting things to happen any day.....which is silly. Most pregnant women wouldn't expect anything to happen for at least another week...........or beyond.
But I'm rubbish. And the waiting is driving me crazy. Every evening I have a whole host of uncomfortable stuff going on down there, including a lovely splitting sensstion on my pelvic floor, strong BH and shooting nerve pains down my legs. It always feels like labour is imminent.....but of course it never is. I've become obsessive about cervical mucus. Which is lovely. It reminds me strongly of the 7 months of TTC last year. I was obsessive about mucus then too.
Quite frankly, being this pregnant It's making me grouchy. I'm sick of getting up 3 or 4 times to wee every night especially.
I am so ready for this. So ready for labour, and so ready to meet my little minicookie. What if I go over my due date? I can't bear the thought. Will I be sat here in 2 wks at 40+4, in a thoroughly foul mood? Aarrrghhhhhhhhhh!
Do I have any other news? I do, but this is a moany, self-indulgent entry, so I'll have to write about that stuff anyother time. For now, there's a tub of Ben & Jerrys with my name on it.