You can use telnet host port.
telnet
www.experts-exchange.com 80 see what the response is.
Then try:
telnet
www.experts-exchange.com 443 and see what the response is.
In a separate window while you try the above, you need to keep refreshing the netstat -an and look at the state of the connection (ESTABLISHED,SYN_WAIT, etc.)
The second part is if you have a webserver elsewhere, you would try to repeat the above examples, but at the same time monitor the network traffic that is hitting your server. Here you will see whether the traffic gets to you which is the first step. Then you see whether your server responded to the connection, but the packets can not find their way back.