Benign Positional Vertigo is quite common with some patients and is caused by sudden movement of the head. BPV is caused by There are some exercises that can be done to help with this. You can click this link and read about how to do them...make sure you have someone with you in case you get dizzy while doing them. They are quite effective when done correctly.
There is a also condition called Meniere's disease that can cause dizziness, however, Meniere's often causes ringing in the ears as well.
Other causes of dizziness could be dehydration, discontinuation of anti-depressant type medications, an oncoming viral infections, migraines, cardiac dsyrhythmias, diabetes, certain medications, decreased blood flow to the brain, and even conditions like MS.
Meclizine is often prescribed for cases in which the cause for the dizziness is unknown.
Hope you feel better soon and reply back if you need any clarification or more info.