I doubt if they will ban you because of one accidental click. Just let them know about it explianing what happened and you should be OK.
jackburton is right.."JESUS" guys just rightclick-propertios-scroll at the end, and you'll see the ads address.. you don't have to click on your own ads each time the ad is interesting.. of course 1-2clicks won't make you ban..try 20-30/day and report here what happend
OH, MY GOSH!! You don't really do that, right? Do yourself a favor and get the Google Adsense Preview Tool to view the targeted ads that can appear on your page (but only if you're using IE, I think). Or get the url to the ad's site and go there directly. My goodness!