If I had a dime for every time I messed up with my plants, I'd be rich.
Anyway, here's one story:
I left my plants with a 'sitter last summer, so I could travel out of state and visit my parents. Because I had to leave on short notice, I had to ask one of my neighbors to take care of my plants. They more than gladly accepted, and I left them my plants. One thing I noticed about their growing area was that it had pretty low light levels, but they knew how to grow the plants, so the low light didn't concern me.
When I came back, I was happy to find that all my plants had made it, and even more so that some had matured new leads.
Here's the "oops" part: I forgot that my growing area is much brighter, and that I had to re-acclimatize my plants to the higher light levels. What happened? Well, to cut a long story short, I burned about five plants. Two didn't make it, but the rest did. I think they're still mad at me for what I did, because they refuse to do anything.
Ever since then, I acclimatize my plants after long periods indoors or in darkness. I've extended the rule to new arrivals, too.
When I forget, my burned plants are quick to remind me what I have to do.
Sorry to hear about your plants. I hope you can save them.