The real question is what did it cost you to get those clicks I like to start with 1%. In other words if 100 people visit my site will I be profitable at 1% conversion rate. If the numbers look good at 1% then I know it looks good and I will most lilkely proceed with the project. So what you have to do is calculate how much 100 visitors will cost you and if you made 1 sale are you profitable or not. Hope that helps
It all depends upon your niche. I have been running a website in a local language not supported by adsense and it earn 0.01 $ per click. Now I changed my niche and have much better results
I think your sample size (just 20 clicks) is a little small to start jumping to any conclusions. I have received as much as $16 for 16 clicks and less than $5 for a different 16 clicks.
As long as it's not too much of a jump from average number of clicks... I always hate having great days since I'm afraid Google will think it's fraud haha.