Tone it down guys. While I would certainly advise seeking medical attention just to be sure, let's be realistic - 6g of APAP is a lot, but many BLers (including myself) have taken 8g or more in a single day and had no liver damage to show from it. And nausea is very a common side effect of taking opiates, it's far more likely that the OP's nausea is caused by the hydrocodone than the APAP.
OP, while you should definitely go to a doctor within the next day or two and have your liver function checked, unless you have pre-existing problems in that department, it's very unlikely that you'll end up with any long term damage from this one occurrence. Unless other symptoms start appearing, there's no cause to rush off to the emergency room or freak yourself out thinking you're about to die.
Just don't do it again in the future, a Cold Water Extraction (CWE) can easily separate the hydrocodone and the APAP with 10 minutes effort, so straining your liver to get high is completely unnecessary. You can easily find out how to do the extraction from google, or PM me and I'll give you instructions.
Likewise, look into a decent nausea medication to take with your opiates so you don't waste your high hunched over a sink.