Conventional wisdom I've read in past forum posts says a second or two will heat up the windings, but won't damage the motor. Prompted by your question to learn a bit more, I searched on damage electric motor by stalling
. That led me to forums on power tools and Wikipedia. The excerpt from A Solar Car Primer
referenced by Stall Torque
sums it up nicely:
Eric F. Thacher wrote:Stall Torque. Suppose the torque loading the shaft increases until the motor stalls. In this condition the shaft power is zero and the current may be large. When stalled, all electrical power supplied to the motor is converted to heat. Consequently the temperature is high, and damage may result. The motor may stall at different torque loads depending on the current available to it. The largest stall torque the motor can endure without damage is called the maximum continuous stall torque.
References aside, if the motor still works, the damage clearly wasn't fatal. I've stalled motors myself, but only for a second or two. I'm with Ira: You're fine.