Open Question: how much acetaminophen is dangerous?

is taking about 3500-4000mg of acetaminophen in a 4-5 hour period dangerous, cause last night i did that by accident, ( was high and took the wrong pain pills) and i am not sure if this is at all related, but today i have not been feeling my best, (lots of.....gas) and i have just been feeling somewhat sick, (might just be because of the gas) but yea, any answer is apreciated