Warframe -- Glitching into (onto) the floor

I was playing a few missions with Zephyr (https://www.twitch.tv/zephyrfloofyderg) today and got some crazy lag, and the game glitched so bad that it showed me as on the floor and sliding about . I ended up ALT+F4ing out of the game then reloading. Eventually, one of the players left and suddenly my lag disappeared.