How can I find out what happened to my transaction?
I'm assuming by asking where the payment went, you're asking how to find the transaction output address. If you have the transaction ID, you can search for it on a site like https://blockchain.info/. Then look for the output address. 

If you don't have the transaction ID, but you have your original Gladiacoin wallet address, you can look up the Gladiacoin wallet address on https://blockchain.info/ and see what transactions were made that way.