Need tools to diagnose port problem.

I'm trying to diagnose why I can not access an internet camera from outside my local network. Camera works fine inside my network, but it is not accessible from the outside. I'm trying to determine if my ISP is blocking a port or if my router is blocking the port, or if the camera has a problem.

I asked my son who lives a few states away to try my external ip address and port while I tried various changes to the router (that is another story about customer support - 5 live chats). Without bothering him again is there a website that I could enter in my URL to see if that website can access my port?

Do you have the router correctly forwarding the port(s) to the right computer within your network?