When I try to login, page failed to load then it brings to error page "Something went wrong"
This error also occurred to me :(
same here...
Apparently it is a real issue and they are trying to address it
https://status.bitbucket.org/
Internal server error :(
same
Now, internal server error: 500 :(
Seems Atlassian have an issue with some of the Cloud installs. Raise it with https://support.atlassian.com/contact to make sure they know your system is affected