azuly - are your muscles tense/clenched while you're dowsing? Some people clench their arm/hand muscles because they don't want to be the one making it move. But it's best to have a somewhat relaxed arm while you dowse. Answers come from your higher self, via your subsconscious mind, which makes the movements happen, so a smaller movement often indiciates your answers are coming through but you're too tense.

Another possibility could be that you're holding your hand too far up/too close to the pendant. I have found that holding my hand halfway down the cord (not at the top) works best for me. Holding my hand at the top means a smaller, slower movement. Every pendulum is different though, it's good to experiment.