How do I know if I am having an emergency and should call 911? 
If you find yourself in a situation that you cannot handle, for whatever reason, that is an emergency and you should call 911.

When I call 911, they ask me a lot of questions about my emergency. Shouldn't they dispatch an ambulance right away? 
While the ambulance is on the way, the 911 operators are asking you for more information, which they can relayed to the paramedic.

Does a State of Emergency mean you aren’t allowed to go anywhere or do anything until it’s lifted?

The Governor’s declaration does not normally restrict citizen movements or activities. The State may limit access to affected areas due to concerns for public safety but will notify the public of these restrictions.