I have delusions and hallucinations, but no sign of stroke, what is this?

Not usually. Stroke in the back of the brain can present with visual hallucinations or even blindness. However, most stroke patients (88% in one study) present with asymmetric facial weakness, arm weakness and or speech difficulty. Delusions and hallucinations are clearly not normal - see a primary care provider as soon as possible to find out what is causing these symptoms.