I left the hot glue on…..for a week!
I was not using the hot glue gun for embroidery (I know....this is an embroidery blog, as of now anyways). It had been used for another craft last weekend. I come back into my craft room the following weekend, about 8 days later) to clean up a little bit, and reached for the glue gun and OUCH! It was so hot! Realizing I hadn't used it in a week, I let it cool off and put it away.
So, I used it yesterday to test it out, praying it wasn't damaged, and spoiler alert: it wasn't! At first I thought the gun was ruined, the glue was coming out brown (take a look at the bottom right glob of glue), the more I squeezed out, the more yellow it became (below on the burlap section). The yellow color wasn't a big deal because it wasn't showing through to the other side. The glue eventually turned back to the original color, clear, once I squeezed out enough.
So if you ever leave the glue gun on for a week, just know it will be okay! No funny smells, no house fires, no ruined glue sticks either, everything turned out just fine.