Congratulations on your beautiful birth! Well done! Your Harriet's story sounds a lot like my Lucy's story - and she is an absolutely beautiful girl with loads of spunk - always wanting to know what's going on. I would say that's Harriets story too - like Lucy she wasnt' wasting any time and wanted to start her life NOW!!!!
Those precipitous labours feel just like you describe - being hit by a truck!

Welcome to this world Harriet!