This has been hapenning since yesterday. Could anyone give me some insight?
it may play into your circumstance.
Quick ideas:
Did you examine your logs for http pages? You may have someone refreshing to see ad variations etc for your pages, which you won't count as uniques but G may count as impressions? (doesn't account for clicks)
Did you triple check your tracking tags? I know it sounds silly, but soemtimes it's just a misleading error.
Is your uniques trackign in JS? Could it be that you've got a JS error somewhere and many people are seeing without getting counted?
You may want to inquire with G about click fraud... they can take a look at the raw on their side for odd behavior.
I did a search for over 10 of the exact matching keywords I have up and none of them are appearing on google, yet I am being charged for them as I see the click going up and up.
More on this later in the afternoon (unless someone beats me to it), but I'm betting this is a daily budget issue - where your daily budget is lower than it would need to be for your ad to show 24/7 for all keywords.
AWA
Most common reasons ads aren't shown [webmasterworld.com]