Here are 2 threads to look at
The frozen insulin test, which @Chris did first and then I did it also.
The Great Frozen Insulin Experiment....part 2.
And then the baked insulin test. This was great.
"Car baked" insulin. An experiment for Irish.
As @Sam said, don’t stress about the temperature. I wouldn’t advise letting it sit in your car like I did, but it still works after a lot of temperature abuse. I got through college without ever refrigerating my insulin.