Both yesterday and…
Both yesterday and today, I have come perilously close to being mean to people on the internet. This is not my normal mode, but lord, I have had no patience with fools lately. Query: do you think Sunday night's car accident could have affected my personality? Query the second: how long do you think this will last? Because if this is the way I'm going to be from now on, I'm going to have to rethink my whole teaching style, for starters.
Could it be a consequence of the new diet instead? Maybe you are reading the fools on the internet while craving sugar.
When you see your doctor, mention this. It’s more likely due to stress and the new diet, but even minor accidents can affect how you react to things.