getting error message "too many connections"
Two thoughts:

1) any chance you have a very low limit by default in your hosting setup/config?
Can you get into MySQL and figure out the value of this variable: 

show variables like 'max_connections';


2) could you be under brute force attack - e.g. against the login form? Can you see any extra/unusual load on your server. If you can get to a shell you can type the following command:

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