All your steps are right, I'd do the same. I'm sure everything is fine with your SQL Server.
I guess it's firewall, try to turn it off or run this from command prompt:
netsh firewall set portopening protocol = TCP port = 1433 name = SQLPort mode = ENABLE scope = SUBNET profile = CURRENT
Also, check if you have antivirus software or something similar and turn it off (on both sides).