Whether or not your error message is a case for concern depends on how well your internet connection works. That said, there clearly is something going on that can be fixed, and that fixing is likely going to involve your current network/hardware settings.
To do that we'd need to know some more about your network hardware, and specifically what kind of router, modem or gateway (modem/router combo) you have*, and (if you know that) how these components are configured (for example 'bridge', 'router', or 'NAT' mode).
*) Please list everything in this category that you currently have hooked up.
