2011 GMC Sierra 2500HD crept from a stop

I have a 2100 gmc seria 2500hd with Duramax desiel and Allison 6 speed transmission. Last night it would only creep away from a stop. No lights or warning messages. Seems to work fine now.

Not enough info there. When you say it would only creep away, was the engine revving and vehicle speed not increasing, or was the engine not responsive?