Google Adwords Jacked My Rates

So here is a question. I am advertising with Google Adwords to do some experimenting. I am advertising a few articles I have up. For the first week it was costing me 6 cents per click which was expensive ( its a content page im advertising ) and then suddenly google has increased it to 12 cents on me.

There is nobody else advetising for my terms since its highly targetted and the site im advertising is a GOOD content site that is 100% related to the ad im running. So the question becomes whats with the rate jack?

Anyone have any suggestions or perhaps a suggestion for me other then adwords for targetted advertising. This indiscriminate jacking of the price really is quite frustrating.

When in your one of your adgroups, click on "Customise Columns" (text link in the green bar at the top) - then scroll down the list to "Show Quality Score" - this will show you if your keywords have been effected by the quality score.

I just had one where I was advertising a English as a foreign language school with the keyword "English Course" - Google had increased my cpc to over $1.

I asked why this was, and they said it wasn't relevant (?????)

All my keywords were on phrase match - so I changed them to broad - and the price was reduced again!!!!!