Limp mode?

Last Friday I drove across town to pick up the wife and kids to head to the cottage. Car worked fine through 20 minutes of moderate traffic in 70F temps. I stopped and turned off the car for like 5 minutes to get them loaded, then started out again. I stalled the car backing out (way to go dad :banghead, which is unusual, but I thought that it was just me. It starts right back up and I head out on the road. The car revs a little and then just bucks and jerks like it can't rev anymore than about 2000rpm. I can barely accelerate. I notice that when I push the clutch in and let it idle, the RPM's are around 1100 (not the normal 600-700 like when it is warm). There was no SES light at all. I drove for a couple of miles until I found a safe spot to turn off and stop. I noticed a very rich smell from the exhaust before I shut it down. I let it set a minute or two, and then restarted it. It has been fine ever since (about 300 miles so far). Does this sound like limp mode?

Anyone want to take a guess at a possible cause?