You can check if your cooler is good enough by downloading prime95 and run a stress test, it would likely show you that the stock cooler by intel is utterly crap.
IF you were to upgrade, then I can recommend the Seidon 120M. I'm using an i5-3570 too and the cooling performance compared to the price is just insane. http://www.youtube.com/watch?v=wOYJoRc1Ci8
- I tried my best to make a review on it. Take a look.
The Intel Stock cool reached 87 celcius and the Seidon 120m only reached 59 celsius in my tests at 100% load. The intel stock cooler was running at 100% and the Seidon 120m only at 74%. If you would like cooler temperatures and lower noise then you should look for a better cooler.