I had been playing a game earlier when I started lagging, not abnormal though it was happening sporadically over the period of about an hour, which is pretty weird for me. I went to check my router to see if someone was pinging me, and I saw a ton of requests blocked from my own IP, all coming from the 50-55k port range. Does anyone have an idea what might have caused this?
This sounds like someone may have been spoofing your IP address to obscure their actual source address, and sending extraneous data your way to saturate your connection.
This is just speculation, as without knowledge of your network, or even what you consider 'your IP' (the local IP address on your system, the public IP of your broadband connection, the IP of your router's WAN interface), I can't say for sure if the dropped traffic was sourced by your devices, or came from the Internet.