Curious about pregnancy and frights

Killer Tomato

So, every so often I have this sort of waking dream where I open my eyes and look next to me on the bed and see a giant spider. It takes a few minutes for me to really wake up and realize that there probably is no actual giant spider, but by this time I have usually shaken poor DH awake, turned on the light, and pulled half the sheets off the bed.

Needless to say, this generally gets my adrenaline going pretty good. Last night the nonexistent giant spider was on the shelf above my head. All the adrenaline gave me a good spell of AF type cramps, which seem to have been a little more present today as well.

SO, my paranoid question of the day is: can experiencing a fright actually harm a pregnancy? Were the cramps just a coincidence, or have others noticed a similar correlation?