These pedal take a little getting used to. In my experience I have had some silly tumbles from being stationary. Once you get used to them they are really worth the effort. My wife took ages and even had me remove them and put back on conventional pedals. One day I forced the issue, put the looks back on and she persevered. Now she would not go back.
BUT!!! wear a helmet and if you don't buy one straight away!
hAVE FUN