H1 hid xenon bulb problem?

just installed a set of hid bulbs in my nissan altima. it said that the h1's would fit.. but they didn't fit right. it seems like the bulb is too long. so now my lights are shinning upwards insted of straight ahead. has anyone else had this problem? what can i do? should i get a different bulb or should i try to make them fit better.