Even when I have more page impressions and more clicks, the earnings are lower than whith less impressions and clicks. How can this be possible? This is certainly annoying, what for will I increase trafiic in my site if "My earnings" are randomly fluctuating?
The number of impressions is so small that daily variations will occur. However this is perfectly normal. If you had tens of thousands or hundreds of thousands of impressions the amount of clicks would be more smoothed out. Also your CTR seems low. Have you considered borderless ads, changing the position on the page, or different sizes of ads?