I suffer with dizziness. What could be causing it?

Many causes. Dizziness is often multifactorial and it is difficult to diagnose in one doctor visit. The causes can range from neurologic such as from medications, low blood pressure, stroke, sensory impairments, or muscle weakness. It could also be related to the inner ear such as in meniere's disease (dizziness with hearing loss, nausea, vomiting, and roaring sounds) or vertigo (positional dizziness).
Lots of causes. Inner ear problems, such as otolithic dysfnctn, even endolymphatic fistula. Perhaps assoc. With blood pressure, medications, hypothyroidism, anemia, and might wonder if migraine equivalent issue. Some pts have meniere's, others have intracranial problems such as acoustic neuroma, maybe see otolaryngologist and track down. Hope this helps.
Complex issue. Three usual causes for dizziness: drug effect, ear problems, brain problems. Many medications and drugs and even some foods may set off dizziness. Ear infections or ear damage may set off dizziness even following head injury. Brain tumors, strokes, seizures, migraines, all may have associated dizziness. Heart and blood pressure problems may cause dizziness. Get a thorough medical evaluation.