I get this all the time! I don't eat out very often so when I do it's a treat. So when I order something and it doesn't live up to expectations I have massive order regret and it stays with me for days 
Today I went out with a group of friends I hadn't seen for a while. Took ages to pick my meal and when it came even though it was nice, I couldn't stop wishing I'd ordered one of the other options. I'm still thinking about it now, it's like a wasted meal choice, especially as I know it will be months before I'm out again for another meal.
I'm seriously considering getting a takeaway tonight to make up for my disappointment.