C 30 T5 Pedal down, no acceleration, "Service Transmission"

[jack1965]

I just purchased a 2012 C30 T5 R. After driving a couple of days, put in new Bosch plugs and air filter. Next day, it was driving fine, stopped for a red light. Taking off, it would barely accelerate even with pedal to floor, like it was in limp mode, maybe a couple of mph. I believe the message on the info screen said "Transmission Service Urgent". Stopped, waited five minutes, then it was fine. Drove normal. No message on info screen. It is an automatic. Any ideas? Scared to drive it now.