In additon to the excellent answers already there may be a further complication to add to what happened as well. If the wind was strong then you have a significant ground shear effect where the windspeed is lower at ground level than it is 3 feet up and 10 feet up it's even stronger. So if you take off at ground level and assume a climb that does not result in any increase in speed then as you move up into the stronger wind your airspeed can easily drop and the stall results. This will be particularly bad with a heavy and low powered model that is slow to accelerate under the best of conditions and doesn't accelerate worth a hoot while trying to climb. Adding in the high drag from a near stall condition during a minimum airspeed takeoff and you have a wonderful recipe for the crash you had.

Next time taxi down to the other end and take off into the wind.