Day two and already disaster???

[hasshoes]

I planted my tomato seeds three days ago, at night. I'd read that they're supposed to take 7 to 9 days to germinate, but I'm silly and excited, so I lifted up the cover this afternoon, and there was absolutely nothing. When I got home in the early evening , I checked them again (like I said, I'm silly,) and I jumped backwards I was so surprised- several seedlings had sprouted to well over and inch (probably two inches) and many are at the inch level.

How did this happen??!!!! They were covered from light and the temp in my house is 70. Should I just throw them out and start over?!!!!! ACK!!!