problem?

So this happened.



18 hours after I started fermentation, my batch started spitting out through the airlock. I let it sit for another 24 hours, at which point it seemed to have stopped, and then moved it into a new carboy. Question, did I do more damage than good in transferring it?

It's fine.  You need a blow off tube or better yet a bigger fermenter.
I have buckets that are around 9 gallons for my 5 gallon batches and about a 15.9 gallon fermenter for my 10 gallon batches.
No blowout issues.

+1
You just have some happy yeast. Containers with more head space will eliminate that. I know it's debatable about using secondary but your glass jug would be a great secondary after the yeast has finished fermenting.

This is the reason that I went to the 9 gallon plastic fermentation buckets.  I used the blowoff tubes for the longest time, but you soon realize, that the blowoff is taking beer with it too.  I didn't like losing a 1/2 gallon of beer each time I had a fermentation go out the blow out tube.

I've never had one go through the airlock on my 9 gallon plastic fermentation buckets.

As far as your beer goes, it is fine.  The stuff is coming out, not going in.  The only problem is that sometimes the airlock gets blocked and won't let the stuff go out through it, at which point it can build up enough pressure to actually shoot the airlock out of the top of your carboy.  If that happens, you end up with not only a mess on the ceiling and carboy and all around the carboy, but now you have an open fermentation, where nasties can get into your fermentating beer.

Did you remember to sanitize the vessel you transferred to?

I was thinking about your actual question, which was "Did I do more harm than good when transferring it?"

When you transfer too early, sometimes it will cause your fermentation to get stuck.  I think that if that had happened, you'd have mentioned it though.  I've learned that if I use a secondary of any kind, I make sure that the primary is done, by checking gravity or by waiting a long time so that I'm sure it has finished primary.

What was your starting gravity, gravity at racking and expected finishing gravity?