I tried to install a forum to my my website a few weeks ago and because of my poor knowledge in working in cPanel, I erased my website's database by mistake. At that moment I had 5-700 visitors every day. It took me a few days to reconstruct my site, but since than my traffic has decreased significantly. Is it possible that google placed my site into this "sandbox"?
Before this "accident" I was on first page for a few keywords on Google Image search, but after that I'm can't find my site even on page 10.