tdewtx's comment "when in doubt throw it out" is a good rule of thumb. If you're not sure, it's always better to start over.
Most likely explanation
But...there's a good chance that this is a harmless yeast colony. It's hard to tell from the small pictures, but this kind of thing is extremely common in fermentation and is referred to as "kahm."
You can read a description here. Sandor Katz, a lacto-fermentation guru, has a great 2-ish minute explainer (with a minor promotional comment at the end). And there are lots of "delightful" kahm pictures here.
Why this is likely
There are two reasons to think this is just kahm.
- In my experience, carrots are more likely to develop kahm than most other ferments. I assume this is due to their high sugar content.
- You mentioned a faint alcohol smell. Often when people say this, they mean beer or wine, i.e., yeast.
What to do next time
To address this if it happens in the future, never let a ferment run 2-3 weeks before checking it. Especially for the first couple of weeks, I check every day or two. That way I can scrape off anything unpleasant before it becomes widespread.
When kahm is widespread, I throw out the ferment—not for safety reasons, but because it tends to impart a yeasty flavor to the vegetables. But when there's just a little at a time, as long as it's not actually in contact with the submerged vegetables, and if I'm confident it's yeast, I scrape it off and continue.