no earning

I was excited to see that my blog earned more than $7 in first few hours (3 0r 4 page impressions and 3 or clicks). But there is no change in page earning since then. Now shows 78 page impressions, 8 clicks but no change in earning? Why is it so? Please help.

I was excited to see that my blog earned more than $7 in first few hours (3 0r 4 page impressions and 3 or clicks). But there is no change in page earning since then. Now shows 78 page impressions, 8 clicks but no change in earning? Why is it so? Please help.