My HEAT client is forging butnl itseems as though the block numbers are not tuencurrent ones. For example thebpast one was
block height # 667886
Does this mean I am mining/forging on the wrong chaine or something?

You can compare the latest pushed block from your server log with the blockchain explorer in Heat Wallet. At this very moment, the latest block is #846056 (13578340254574920229), pushed at 2017-11-19 12:57:00.
So you do not seem to be in sync. Are you running the latest server? You could delete the blockchain folder and try again. Always wait for the server to be fully in sync before starting to forge.