I believe this happens often. For me it is usually when I visit a nursery and see something that is just a bit too expensive and so I don't get it. Then, when I get home and unpack whatever I did get - I usually regret not just getting the plant that interested me instead of two more hybrids of something else. LOL.
But, like everything in life, things come around again and again. Patience is the key and going with your first instinct is the goal rather than second guessing. hahaha....