Blogger on Tuesday, March 30, encountered a 502 error and was down for about 10 minutes thereby affecting the login page, the comment system, Blogger Status, Blogger Buzz and perhaps other services.
We had a hard time logging in to our account and we were somehow scared.

Checkupdown, a good source of information about internet error codes, explains what cause a 502 error:
We still don't have enough information as to what really happened. We hope Blogger will issue an official statement about the downtime soon.
Whoelse had the same experience?
We had a hard time logging in to our account and we were somehow scared.
- This problem is due to poor IP communication between back-end computers, possibly including the Web server at the site you are trying to visit. Before analysing this problem, you should clear your browser cache completely.
- If you are surfing the Web and see this problem for all Web sites you try to visit, then either 1) your ISP has a major equipment failure/overload or 2) there is something wrong with your internal Internet connection e.g. your firewall is not functioning correctly. In the first case, only your ISP can help you. In the second case, you need to fix whatever it is that is preventing you reaching the Internet.
- If you get this problem for only some of the Web sites you try to visit then it is likely to be a problem at those sites i.e. one of their pieces of equipment is failing/overloaded. Contact the people at those sites.
We still don't have enough information as to what really happened. We hope Blogger will issue an official statement about the downtime soon.
Whoelse had the same experience?