Obtaining Orgasm!

I love sex in every which way possible and often orgasm, multiple times. In less that five minutes, just using his hand for clitoral stimulation, my boyfriend can make me orgasm. However, when I play alone, unless really really in the mood, there are alot of times which I will be using a handy massager with strong vibrations against my clit and will never orgasm! It's frustrating. Has this happened to anyone? Any suggestions? Maybe I'm just not mentally there at the moment??