My mouse is acting up and once yesterday I clicked on an adsense ad from my primary computer and, I got that kinda blood rush to your head feeling. I wrote Adsense, told them and apologized. I gave them the exact ad, from page and Ip address and asked them to disregard the click and I was very sorry.
This morning, I did the same $%#$@ thing, I thought I was having a heart attack, I still might.... I just wrote them, same apology and I hope the best.
As someone whose cordless mouse just decided to go whacko in the middle of a phone call with an advertiser, I can relate to your story, edge.
I hope all is well, and that no visits to the emergency room were required!
Although I am not associated with the AdSense program at all, I have been with the AdWords team for a couple of years now - and I know what Google is about. I can say with assurance that a couple of accidental clicks (especially followed up with an explanation!) should not be cause for further worry.