I've discovered I'm a really shitty conversationalist when I've had way too much coffee and worked an 11 hour shift after having only 4 hours of sleep in the past 4 days prior to the talking. I don't think I even make sense. I apologize to anyone I've talked to a few days ago. I'm a lot more lively when I'm out and drinking and have had no coffee and at least 4 hours of sleep in '1' day. Need sleep, must resist coffee..... 
More sleep, less coffee!!!!