Firewall Packet Drops

[#1]

For the last week now my router has been logging firewall packet drops can anyone tell me if I should be worried? They were all the same until today I noticed Firewall packet drops from I presume an ip address to my ip address Protocol ICMP, Message type 8 or type 3?

[#2]

ICMP type 3 is destination host unreachable, basically a response code to indicate that the requested destination cannot be reached either due to a problem or perhaps even a firewall policy.
Could even be as simple as trying to send a packet to a device that's gone offline.
Type 8 Is ICMP echo, basically a Ping (are you there?)

[#3]

Thanks dragon2611 for your reply I presume its nothing to be worried about then?

[#4]

not unless your running a server, although most of them no longer accept icmp requests either

[#5]

I rebooted the router, not had any of them messages show up in the logs since. Dodgy IP address?