04 lost rear freeze plug

I lost my rear freeze plug in my 04 and I had no choice but to drive the truck home for 45 minutes in the middle of the night because I had no cell service wasn't sure what the problem was at the time. The coolant temp didn't get above 220 but don't know how accurate that was because of the loss of coolant. My question is do I throw a freeze plug in it and run it or should I consider tearing into the engine. What are some things that could be damaged internally I should be worried about????