My visitors have increased quite rapidly: are the stats playing a game?

I don't know how my visitors reached from 800 to 1,595 to 2,000 to 4,587!! Its almost reaching 5,000 visitors and that's not really bad, ha? But the most confusing thing is that how come between a one day span, my visitors have increased quite rapidly.. like from 2,000 to 4,587. Do you think its fishy, possible or incorrect stats? Please let me know.. I am used to traffic as high as this but that was before..

Its true that i used to have about 2,000 and more visitors before the month of may, and it was possible because i was blogging from July 2007. The very disheartening decrease happened when i wasn't active for almost 40 days, month of may.. my visitors dropped to just 200 something:(.. A few posts and activeness on forums, communities etc got me back to square one and now this big big increase.. but hopefully it should continue this way, if there is nothing fishy:)